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• centos 6 ps aux hangs up

  - by Guntis

  I have problem with my server. Server is running centos 6 (CloudLinux Server release 6.2). uname -a = 2.6.32-320.4.1.lve1.1.4.el6.x86_64 That is a kvm guest. On host is debian 6. If i run command ps aux, it stuck on random process (shows some processes only), top command is working fine. htop doesn't work too (black screen). top - 12:11:51 up 34 min, 1 user, load average: 4.26, 6.71, 16.15 Tasks: 201 total, 7 running, 192 sleeping, 0 stopped, 2 zombie Cpu(s): 7.9%us, 2.8%sy, 0.0%ni, 87.5%id, 1.6%wa, 0.0%hi, 0.2%si, 0.0%st Mem: 9862044k total, 2359484k used, 7502560k free, 171720k buffers Swap: 10485720k total, 0k used, 10485720k free, 1336872k cached server has one Intel(R) Xeon(R) CPU E5606 @ 2.13GHz, free -m total used free shared buffers cached Mem: 9630 2336 7293 0 170 1324 -/+ buffers/cache: 841 8789 Swap: 10239 0 10239 php -v PHP 5.3.19 (cli) (built: Nov 28 2012 10:03:07) Copyright (c) 1997-2012 The PHP Group Zend Engine v2.3.0, Copyright (c) 1998-2012 Zend Technologies with the ionCube PHP Loader v4.2.2, Copyright (c) 2002-2012, by ionCube Ltd., and with Zend Guard Loader v3.3, Copyright (c) 1998-2010, by Zend Technologies with Suhosin v0.9.33, Copyright (c) 2007-2012, by SektionEins GmbH mysql Server version: 5.1.63-cll php -i disable_functions => apache_child_terminate, apache_setenv, define_syslog_variables, escapeshellarg, escapeshellcmd, eval, exec, fp, fput, ftp_connect, ftp_e xec, ftp_get, ftp_login, ftp_nb_fput, ftp_put, ftp_raw, ftp_rawlist, highlight_file, ini_alter, ini_get_all, ini_restore, inject_code, openlog, passthru, php _uname, phpAds_remoteInfo, phpAds_XmlRpc, phpAds_xmlrpcDecode, phpAds_xmlrpcEncode, popen, posix_getpwuid, posix_kill, posix_mkfifo, posix_setpgid, posix_set sid, posix_setuid, posix_setuid, posix_uname, proc_close, proc_get_status, proc_nice, proc_open, proc_terminate, shell_exec, syslog, system, xmlrpc_entity_de code, xmlrpc_server_create, putenv, show_source,mail => apache_child_terminate, apache_setenv, define_syslog_variables, escapeshellarg, escapeshellcmd, eval, exec, fp, fput, ftp_connect, ftp_exec, ftp_get, ftp_login, ftp_nb_fput, ftp_put, ftp_raw, ftp_rawlist, highlight_file, ini_alter, ini_get_all, ini_restore, inject_code, openlog, passthru, php_uname, phpAds_remoteInfo, phpAds_XmlRpc, phpAds_xmlrpcDecode, phpAds_xmlrpcEncode, popen, posix_getpwuid, posix_kill, pos ix_mkfifo, posix_setpgid, posix_setsid, posix_setuid, posix_setuid, posix_uname, proc_close, proc_get_status, proc_nice, proc_open, proc_terminate, shell_exe c, syslog, system, xmlrpc_entity_decode, xmlrpc_server_create, putenv, show_source,mail ... suhosin.executor.disable_eval => Off => Off suhosin.executor.eval.blacklist => include,include_once,require,require_once,curl_init,fpassthru,base64_encode,base64_decode,mail,exec,system,proc_open,leak, syslog,pfsockopen,shell_exec,ini_restore,symlink,stream_socket_server,proc_nice,popen,proc_get_status,dl, pcntl_exec, pcntl_fork, pcntl_signal,pcntl_waitpid, pcntl_wexitstatus, pcntl_wifexited, pcntl_wifsignaled,pcntl_wifstopped, pcntl_wstopsig, pcntl_wtermsig, socket_accept,socket_bind, socket_connect, socket_cr eate, socket_create_listen,socket_create_pair,link,register_shutdown_function,register_tick_function,gzinflate => include,include_once,require,require_once,c url_init,fpassthru,base64_encode,base64_decode,mail,exec,system,proc_open,leak,syslog,pfsockopen,shell_exec,ini_restore,symlink,stream_socket_server,proc_nic e,popen,proc_get_status,dl, pcntl_exec, pcntl_fork, pcntl_signal,pcntl_waitpid, pcntl_wexitstatus, pcntl_wifexited, pcntl_wifsignaled,pcntl_wifstopped, pcntl _wstopsig, pcntl_wtermsig, socket_accept,socket_bind, socket_connect, socket_create, socket_create_listen,socket_create_pair,link,register_shutdown_function, register_tick_function,gzinflate Sometimes i cannot kill httpd process. I run kill -9 PID even several times, and nothing happens. php runs via suphp. I learned somewhere that it can be trojan. I ran strace ps aux and it stops on open("/proc/PID/cmdline", O_RDONLY) If i reboot server, problem is gone but after some time it is back again .. :( Thanks.

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• Recommendations or advice for shared computer control

  - by Telemachus

  Basic scenario: we are a school (overwhelmingly Mac, some Windows machines via BootCamp), and we are considering using DeepFreeze to guard the state of our shared machines. We have roughly 250 machines that are either shared laptops (which move around quite a bit) or common desktops in public spaces. Obviously, we spend a lot of time maintaining the machines and trying to reverse the inevitable drift as people make changes to the computers. We would like to control the integrity of the build we initially put onto the machines without handcuffing users and especially without using Mac's Parental Control software. (We've had nothing but bad experiences with it.) We've been testing DeepFreeze, and so far it's very impressive. But I'm curious to hear if people who have used DeepFreeze or any similar software have any advice or tips. To get things started, I will post my own pros and cons. Pros: The state of the machine is frozen in our chosen state. All changes made to the machine after that disappear upon restart. (This frozen state really appears to cover everything. I have yet to do something to a test machine that isn't instantly healed.) Tons of trivial but time-consuming maintenance is gone in an instant. Also, lots of not-so-trivial breakage should be avoided. There are good options, however, that allow you to create storage spaces either globally or per user. (Otherwise, stored files disappear upon reboot. For some machines, this is a good option itself. Simply warn people: save externally or else; this machine is a kiosk, not your storage space.) Cons: Anytime we actually need to make a change (upgrade basic software, add a printer or an airport permanently, add new software), the process is a bit more complex. Reboot into a special mode (thaw state), make changes, reboot back into frozen mode. If (when?) we forget this, we will end up making changes that disappear after the next reboot. Users will forget to save files correctly (in the right place or externally), and we will have loud, unpleasant conversations explaining that we can't recover the document they worked on all afternoon yesterday. The machine rebooted. The file is gone. These are my initial thoughts, but I would love to hear from other people who have experience with DeepFreeze or any similar software. What should we be careful about? Do the pros outweigh the cons? What gains or problems am I not seeing? Thanks.

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• May 20th Links: ASP.NET MVC, ASP.NET, .NET 4, VS 2010, Silverlight

  - by ScottGu

  Here is the latest in my link-listing series.  Also check out my VS 2010 and .NET 4 series and ASP.NET MVC 2 series for other on-going blog series I’m working on. [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] ASP.NET MVC How to Localize an ASP.NET MVC Application: Michael Ceranski has a good blog post that describes how to localize ASP.NET MVC 2 applications. ASP.NET MVC with jTemplates Part 1 and Part 2: Steve Gentile has a nice two-part set of blog posts that demonstrate how to use the jTemplate and DataTable jQuery libraries to implement client-side data binding with ASP.NET MVC. CascadingDropDown jQuery Plugin for ASP.NET MVC: Raj Kaimal has a nice blog post that demonstrates how to implement a dynamically constructed cascading dropdownlist on the client using jQuery and ASP.NET MVC. How to Configure VS 2010 Code Coverage for ASP.NET MVC Unit Tests: Visual Studio enables you to calculate the “code coverage” of your unit tests.  This measures the percentage of code within your application that is exercised by your tests – and can give you a sense of how much test coverage you have.  Gunnar Peipman demonstrates how to configure this for ASP.NET MVC projects. Shrinkr URL Shortening Service Sample: A nice open source application and code sample built by Kazi Manzur that demonstrates how to implement a URL Shortening Services (like bit.ly) using ASP.NET MVC 2 and EF4.  More details here. Creating RSS Feeds in ASP.NET MVC: Damien Guard has a nice post that describes a cool new “FeedResult” class he created that makes it easy to publish and expose RSS feeds from within ASP.NET MVC sites. NoSQL with MongoDB, NoRM and ASP.NET MVC Part 1 and Part 2: Nice two-part blog series by Shiju Varghese on how to use MongoDB (a document database) with ASP.NET MVC.  If you are interested in document databases also make sure to check out the Raven DB project from Ayende. Using the FCKEditor with ASP.NET MVC: Quick blog post that describes how to use FCKEditor – an open source HTML Text Editor – with ASP.NET MVC. ASP.NET Replace Html.Encode Calls with the New HTML Encoding Syntax: Phil Haack has a good blog post that describes a useful way to quickly update your ASP.NET pages and ASP.NET MVC views to use the new <%: %> encoding syntax in ASP.NET 4.  I blogged about the new <%: %> syntax – it provides an easy and concise way to HTML encode content. Integrating Twitter into an ASP.NET Website using OAuth: Scott Mitchell has a nice article that describes how to take advantage of Twiter within an ASP.NET Website using the OAuth protocol – which is a simple, secure protocol for granting API access. Creating an ASP.NET report using VS 2010 Part 1, Part 2, and Part 3: Raj Kaimal has a nice three part set of blog posts that detail how to use SQL Server Reporting Services, ASP.NET 4 and VS 2010 to create a dynamic reporting solution. Three Hidden Extensibility Gems in ASP.NET 4: Phil Haack blogs about three obscure but useful extensibility points enabled with ASP.NET 4. .NET 4 Entity Framework 4 Video Series: Julie Lerman has a nice, free, 7-part video series on MSDN that walks through how to use the new EF4 capabilities with VS 2010 and .NET 4.  I’ll be covering EF4 in a blog series that I’m going to start shortly as well. Getting Lazy with System.Lazy: System.Lazy and System.Lazy<T> are new features in .NET 4 that provide a way to create objects that may need to perform time consuming operations and defer the execution of the operation until it is needed.  Derik Whittaker has a nice write-up that describes how to use it. LINQ to Twitter: Nifty open source library on Codeplex that enables you to use LINQ syntax to query Twitter. Visual Studio 2010 Using Intellitrace in VS 2010: Chris Koenig has a nice 10 minute video that demonstrates how to use the new Intellitrace features of VS 2010 to enable DVR playback of your debug sessions. Make the VS 2010 IDE Colors look like VS 2008: Scott Hanselman has a nice blog post that covers the Visual Studio Color Theme Editor extension – which allows you to customize the VS 2010 IDE however you want. How to understand your code using Dependency Graphs, Sequence Diagrams, and the Architecture Explorer: Jennifer Marsman has a nice blog post describes how to take advantage of some of the new architecture features within VS 2010 to quickly analyze applications and legacy code-bases. How to maintain control of your code using Layer Diagrams: Another great blog post by Jennifer Marsman that demonstrates how to setup a “layer diagram” within VS 2010 to enforce clean layering within your applications.  This enables you to enforce a compiler error if someone inadvertently violates a layer design rule. Collapse Selection in Solution Explorer Extension: Useful VS 2010 extension that enables you to quickly collapse “child nodes” within the Visual Studio Solution Explorer.  If you have deeply nested project structures this extension is useful. Silverlight and Windows Phone 7 Building a Simple Windows Phone 7 Application: A nice tutorial blog post that demonstrates how to take advantage of Expression Blend to create an animated Windows Phone 7 application. If you haven’t checked out my Windows Phone 7 Twitter Tutorial I also recommend reading that. Hope this helps, Scott P.S. If you haven’t already, check out this month’s "Find a Hoster” page on the www.asp.net website to learn about great (and very inexpensive) ASP.NET hosting offers.

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• Leaks on Wikis: "Corporations...You're Next!" Oracle Desktop Virtualization Can Help.

  - by adam.hawley

  Between all the press coverage on the unauthorized release of 251,287 diplomatic documents and on previous extensive releases of classified documents on the events in Iraq and Afghanistan, one could be forgiven for thinking massive leaks are really an issue for governments, but it is not: It is an issue for corporations as well. In fact, corporations are apparently set to be the next big target for things like Wikileaks. Just the threat of such a release against one corporation recently caused the price of their stock to drop 3% after the leak organization claimed to have 5GB of information from inside the company, with the implication that it might be damaging or embarrassing information. At the moment of this blog anyway, we don't know yet if that is true or how they got the information but how did the diplomatic cable leak happen? For the diplomatic cables, according to press reports, a private in the military, with some appropriate level of security clearance (that is, he apparently had the correct level of security clearance to be accessing the information...he reportedly didn't "hack" his way through anything to get to the documents which might have raised some red flags...), is accused of accessing the material and copying it onto a writeable CD labeled "Lady Gaga" and walking out the door with it. Upload and... Done. In the same article, the accused is quoted as saying "Information should be free. It belongs in the public domain." Now think about all the confidential information in your company or non-profit... from credit card information, to phone records, to customer or donor lists, to corporate strategy documents, product cost information, etc, etc.... And then think about that last quote above from what was a very junior level person in the organization...still feeling comfortable with your ability to control all your information? So what can you do to guard against these types of breaches where there is no outsider (or even insider) intrusion to detect per se, but rather someone with malicious intent is physically walking out the door with data that they are otherwise allowed to access in their daily work? A major first step it to make it physically, logistically much harder to walk away with the information. If the user with malicious intent has no way to copy to removable or moble media (USB sticks, thumb drives, CDs, DVDs, memory cards, or even laptop disk drives) then, as a practical matter it is much more difficult to physically move the information outside the firewall. But how can you control access tightly and reliably and still keep your hundreds or even thousands of users productive in their daily job? Oracle Desktop Virtualization products can help.Oracle's comprehensive suite of desktop virtualization and access products allow your applications and, most importantly, the related data, to stay in the (highly secured) data center while still allowing secure access from just about anywhere your users need to be to be productive.  Users can securely access all the data they need to do their job, whether from work, from home, or on the road and in the field, but fully configurable policies set up centrally by privileged administrators allow you to control whether, for instance, they are allowed to print documents or use USB devices or other removable media.  Centrally set policies can also control not only whether they can download to removable devices, but also whether they can upload information (see StuxNet for why that is important...)In fact, by using Sun Ray Client desktop hardware, which does not contain any disk drives, or removable media drives, even theft of the desktop device itself would not make you vulnerable to data loss, unlike a laptop that can be stolen with hundreds of gigabytes of information on its disk drive.  And for extreme security situations, Sun Ray Clients even come standard with the ability to use fibre optic ethernet networking to each client to prevent the possibility of unauthorized monitoring of network traffic.But even without Sun Ray Client hardware, users can leverage Oracle's Secure Global Desktop software or the Oracle Virtual Desktop Client to securely access server-resident applications, desktop sessions, or full desktop virtual machines without persisting any application data on the desktop or laptop being used to access the information.  And, again, even in this context, the Oracle products allow you to control what gets uploaded, downloaded, or printed for example.Another benefit of Oracle's Desktop Virtualization and access products is the ability to rapidly and easily shut off user access centrally through administrative polices if, for example, an employee changes roles or leaves the company and should no longer have access to the information.Oracle's Desktop Virtualization suite of products can help reduce operating expense and increase user productivity, and those are good reasons alone to consider their use.  But the dynamics of today's world dictate that security is one of the top reasons for implementing a virtual desktop architecture in enterprises.For more information on these products, view the webpages on www.oracle.com and the Oracle Technology Network website.

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• Oracle Database 12c: Oracle Multitenant Option

  - by hamsun

  1. Why ? 2. What is it ? 3. How ? 1. Why ? The main idea of the 'grid' is to share resources, to make better use of storage, CPU and memory. If a database administrator wishes to implement this idea, he or she must consolidate many databases to one database. One of the concerns of running many applications together in one database is: ‚what will happen, if one of the applications must be restored because of a human error?‘ Tablespace point in time recovery can be used for this purpose, but there are a few prerequisites. Most importantly the tablespaces are strictly separated for each application. Another reason for creating separated databases is security: each customer has his own database. Therefore, there is often a proliferation of smaller databases. Each of them must be maintained, upgraded, each allocates virtual memory and runs background processes thereby wasting resources. Oracle 12c offers another possibility for virtualization, providing isolation at the database level: the multitenant container database holding pluggable databases. 2. What ? Pluggable databases are logical units inside a multitenant container database, which consists of one multitenant container database and up to 252 pluggable databases. The SGA is shared as are the background processes. The multitenant container database holds metadata information common for pluggable databases inside the System and the Sysaux tablespace, and there is just one Undo tablespace. The pluggable databases have smaller System and Sysaux tablespaces, containing just their 'personal' metadata. New data dictionary views will make the information available either on pdb (dba_views) or container level (cdb_views). There are local users, which are known in specific pluggable databases and common users known in all containers. Pluggable databases can be easily plugged to another multitenant container database and converted from a non-CDB. They can undergo point in time recovery. 3. How ? Creating a multitenant container database can be done using the database configuration assistant: There you find the new option: Create as Container Database. If you prefer ‚hand made‘ databases you can execute the command from a instance in nomount state: CREATE DATABASE cdb1 ENABLE PLUGGABLE DATABASE …. And of course this can also be achieved through Enterprise Manager Cloud. A freshly created multitenant container database consists of two containers: the root container as the 'rack' and a seed container, a template for future pluggable databases. There are 4 ways to create other pluggable databases: 1. Create an empty pdb from seed 2. Plug in a non-CDB 3. Move a pdb from another pdb 4. Copy a pdb from another pdb We will discuss option2: how to plug in a non_CDB into a multitenant container database. Three different methods are available : 1. Create an empty pdb and use Datapump in traditional export/import mode or with Transportable Tablespace or Database mode. This method is suitable for pre 12c databases. 2. Create an empty pdb and use GoldenGate replication. When the pdb catches up with the non-CDB, you fail over to the pdb. 3. Databases of Version 12c or higher can be plugged in with the help of the new dbms_pdb Package. This is a demonstration for method 3: Step1: Connect to the non-CDB to be plugged in and create an xml File with description of the database. The xml file is written to $ORACLE_HOME/dbs per default and contains mainly information about the datafiles. Step 2: Check if the non-CDB is pluggable in the multitenant container database: Step 3: Create the pluggable database, connected to the Multitenant container database. With nocopy option the files will be reused, but the tempfile is created anew: A service is created and registered automatically with the listener: Step 4: Delete unnecessary metadata from PDB SYSTEM tablespace: To connect to newly created pdb, edit tnsnames.ora and add entry for new pdb. Connect to plugged-in non_CDB and clean up Data Dictionary to remove entries now maintained in multitenant container database. As all kept objects have to be recompiled it will take a few minutes. Step 5: The plugged-in database will be automatically synchronised by creating common users and roles when opened the first time in read write mode. Step 6: Verify tablespaces and users: There is only one local tablespace (users) and one local user (scott) in the plugged-in non_CDB pdb_orcl. This method of creating plugged_in non_CDB from is fast and easy for 12c databases. The method for deplugging a pluggable database from a CDB is to create a new non_CDB and use the the new full transportable feature of Datapump and drop the pluggable database. About the Author: Gerlinde has been working for Oracle University Germany as one of our Principal Instructors for over 14 years. She started with Oracle 7 and became an Oracle Certified Master for Oracle 10g and 11c. She is a specialist in Database Core Technologies, with profound knowledge in Backup & Recovery, Performance Tuning for DBAs and Application Developers, Datawarehouse Administration, Data Guard and Real Application Clusters.

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• Winners of the Oracle Excellence Award—Eco-Enterprise Innovation

  - by Evelyn Neumayr

  Did you get a chance to attend Oracle OpenWorld in San Francisco? With 60,000 attendees and hundreds of sessions to choose from—there was a lot going on. One of my favorite sessions was the Eco-Enterprise Awards and Sustainability Executive Panel Discussion. During this session, Jeff Henley, Oracle Chairman of the Board, announced the winners of the 2013 Oracle Excellence Award—Eco-Enterprise Innovation. It was an enlightening session as we heard several of the winning customers discuss the importance of sustainability to their company and how they’re using various Oracle products to help with their sustainability initiatives. The winning customers include: Centennial Coal, Indaver nv, Korea Enterprise Data, National Guard Health Affairs, Schneider National, SThree, Telstra International Group, Trex Company, University of Salzburg, Walmart, and Yeoncheon County Office. Stay tuned for additional blogs where you’ll learn more about these winning companies’ environmental best practices and why they won this award. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Several partners were also recognized for helping these customers with their sustainability initiatives. Those partners include: CSS International, Daesang Information Technology, i4BI, Infosys, Knowledge Global, Solutions for Retails Brands Limited, and SysGen. During this same session, Jeff Henley also awarded Robert Kaplan, Director of Sustainability at Walmart, with Oracle’s Chief Sustainability Officer of the Year award. Robert was honored for helping improve Walmart’s supply chain efficiency with their Sustainability Hub. The Sustainability Hub, powered by Oracle Service Cloud, is a central location for Walmart suppliers, associates and business partners to learn, connect, inspire and drive sustainability through collaboration. While at Oracle OpenWorld, I also got a chance to hear Robert Kaplan discuss their Sustainability Hub during an Oracle OpenWorld Live taping. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

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• Oracle Delivers Latest Release of Oracle Enterprise Manager 12c

  - by Scott McNeil

  Richer Service Catalog for Database and Middleware as a Service; Enhanced Database and Middleware Management Help Drive Enterprise-Scale Private Cloud Adoption News Summary IT organizations are adopting private clouds as a stepping-stone to business-driven, self-service IT. Successful implementations hinge on the ability to efficiently deploy and manage cloud services at enterprise scale. Having a complete cloud management solution integrated with an enterprise-class technology stack is a fundamental requirement for IT. Oracle Enterprise Manager 12c Release 4 meets that requirement by helping businesses become more agile and responsive, while reducing cost, complexity, and risk. News Facts Oracle Enterprise Manager 12c Release 4, available today, lets organizations rapidly adopt Oracle-based, enterprise-scale private clouds. New capabilities provide advanced technology stack management, secure database administration, and enterprise service governance, enabling Oracle customers and partners to maximize database and application performance and drive innovation using self-service IT platforms. The enhancements have been driven by customers and the growing Oracle Enterprise Manager Ecosystem, comprised of more than 750 Oracle PartnerNetwork (OPN) Specialized partners. Oracle and its partners and customers have built over 140 plug-ins and connectors for Oracle Enterprise Manager. Watch the video highlights. Automation for Broader Cloud Services Oracle Enterprise Manager 12c Release 4 allows for a rapid enterprise-wide adoption of database, middleware and infrastructure services in the private cloud, driven by an enhanced API-enabled service catalog. The release features “push button” style provisioning of complete environments such as SOA and Oracle Active Data Guard, and fast data cloning that enables rapid deployment and testing of enterprise applications. Out-of-the-box capabilities to detect data and configuration vulnerabilities provide enhanced cloud service governance along with greater operational control through a flexible and extensible showback mechanism. Enhanced Database Management A new performance warehouse enables predictive database diagnostics and trend analysis and helps identify database problems before they occur. New enterprise data-governance capabilities enhance security by helping systematically discover and protect sensitive data. Step-by-step orchestration of upgrades with the ability to rollback changes enables faster adoption of Oracle Database 12c. Expanded Fusion Middleware Management A new consolidated view of Oracle Fusion Middleware 12c deployments with a guided management capability lets administrators apply best management practices to diverse middleware environments and identify performance issues quickly. A Java VM Diagnostics as a Service feature allows governed access to diagnostics data for IT workers across multiple disciplines for accelerated DevOps resolutions of defects and performance optimization. New automated provisioning for SOA lets middleware administrators perform mass SOA provisioning with ease. Superior Enterprise-Grade Management Private roles and preferred credentials have been added to Oracle Enterprise Manager to provide additional fine-grained security for organizations with complex access control requirements. A new security console provides a single point of control for managing the security of Oracle Enterprise Manager environments. Support for the latest industry standard SNMP v3 protocol, including encryption, enables more secure heterogeneous management. “Smart monitoring” adapts to observed environmental changes and adds self-management capabilities to help Oracle Enterprise Manager run at peak performance, while demanding less IT supervision. Supporting Quotes “Lawrence Livermore National Laboratory has a strong tradition of technology breakthroughs and leadership. As a member of Oracle’s Customer Advisory Board for Oracle Enterprise Manager, we have consistently provided feedback and guidance in the areas of enterprise-scale cloud, self-diagnosability, and secure administration for the product,” said Tim Frazier, CIO, NIF and Photon Sciences, Lawrence Livermore National Laboratory. “We intend to take advantage of the Release 4 features that support enterprise-scale availability and fine-grained security capabilities for private cloud deployments.” “IDC's most recent CloudTrack survey shows that most enterprises plan to adopt hybrid cloud architectures over the next three years,” said Mary Johnston Turner, Research Vice President, Enterprise System Management Software, IDC. “These organizations plan to deploy a wide range of workloads into cloud environments including mission critical database and middleware services that require high levels of fault tolerance and disaster recovery. Such capabilities were traditionally custom configured for each application but cloud offers the possibility to incorporate such properties within the service definition, enabling organizations to adopt cloud without compromise. With the latest release of Oracle Enterprise Manager 12c, Oracle is providing customers with an out-of-the-box experience for delivering highly-resilient cloud services for databases and applications.” “Since its inception, Oracle has been leading the way in innovative, scalable and high performance solutions for the enterprise. With this release of Oracle Enterprise Manager, we are extending this leadership by providing enterprise-scale capabilities for planning, delivering, and managing private clouds. We call this ‘zero-to-cloud – accelerated.’ These enhancements help our customers to expedite their adoption of cloud computing and prepares them for the next generation of self-service IT,” said Prakash Ramamurthy, senior vice president of Systems and Cloud Management at Oracle. Supporting Resources Oracle Enterprise Manager 12c Video: Cerner Delivers High Performance Private Cloud Video: BIAS Achieves Outstanding Results with Private Cloud Press Release Stay Connected: Twitter | Facebook | YouTube | Linkedin | Newsletter Download the Oracle Enterprise Manager 12c Mobile app

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• How to Answer a Stupid Interview Question the Right Way

  - by AjarnMark

  Have you ever been asked a stupid question during an interview; one that seemed to have no relation to the job responsibilities at all?  Tech people are often caught off-guard by these apparently irrelevant questions, but there is a way you can turn these to your favor.  Here is one idea. While chatting with a couple of folks between sessions at SQLSaturday 43 last weekend, one of them expressed frustration over a seemingly ridiculous and trivial question that she was asked during an interview, and she believes it cost her the job opportunity.  The question, as I remember it being described was, “What is the largest byte measurement?”.  The candidate made up a guess (“zetabyte”) during the interview, which is actually closer than she may have realized.  According to Wikipedia, there is a measurement known as zettabyte which is 10^21, and the largest one listed there is yottabyte at 10^24. My first reaction to this question was, “That’s just a hiring manager that doesn’t really know what they’re looking for in a candidate.  Furthermore, this tells me that this manager really does not understand how to build a team.”  In most companies, team interaction is more important than uber-knowledge.  I didn’t ask, but this could also be another geek on the team trying to establish their Alpha-Geek stature.  I suppose that there are a few, very few, companies that can build their businesses on hiring only the extreme alpha-geeks, but that certainly does not represent the majority of businesses in America. My friend who was there suggested that the appropriate response to this silly question would be, “And how does this apply to the work I will be doing?” Of course this is an understandable response when you’re frustrated because you know you can handle the technical aspects of the job, and it seems like the interviewer is just being silly.  But it is also a direct challenge, which may not be the best approach in interviewing.  I do have to admit, though, that there are those folks who just won’t respect you until you do challenge them, but again, I don’t think that is the majority. So after some thought, here is my suggestion: “Well, I know that there are petabytes and exabytes and things even larger than that, but I haven’t been keeping up on my list of Greek prefixes that have not yet been used, so I would have to look up the exact answer if you need it.  However, I have worked with databases as large as 30 Terabytes.  How big are the largest databases here at X Corporation?”  Perhaps with a follow-up of, “Typically, what I have seen in companies that have databases of your size, is that the three biggest challenges they face are: A, B, and C.  What would you say are the top 3 concerns that you would like the person you hire to be able to address?…Here is how I have dealt with those concerns in the past (or ‘Here is how I would tackle those issues for you…’).” Wait! What just happened?!  We took a seemingly irrelevant and frustrating question and turned it around into an opportunity to highlight our relevant skills and guide the conversation back in a direction more to our liking and benefit.  In more generic terms, here is what we did: Admit that you don’t know the specific answer off the top of your head, but can get it if it’s truly important to the company. Maybe for some reason it really is important to them. Mention something similar or related that you do know, reassuring them that you do have some knowledge in that subject area. Draw a parallel to your past work experience. Ask follow-up questions about the company’s specific needs and discuss how you can fulfill those. This type of thing requires practice and some forethought.  I didn’t come up with this answer until a day later, which is too late when you’re interviewing.  I still think it is silly for an interviewer to ask something like that, but at least this is one way to spin it to your advantage while you consider whether you really want to work for someone who would ask a thing like that.  Remember, interviewing is a two-way process.  You’re deciding whether you want to work there just as much as they are deciding whether they want you. There is always the possibility that this was a calculated maneuver on the part of the hiring manager just to see how quickly you think on your feet and how you handle stupid questions.  Maybe he knows something about the work environment and he’s trying to gauge whether you’ll actually fit in okay.  And if that’s the case, then the above response still works quite well.

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• Changing the sequencing strategy for File/Ftp Adapter

  - by [email protected]

  The File/Ftp Adapter allows the user to configure the outbound write to use a sequence number. For example, if I choose address-data_%SEQ%.txt as the FileNamingConvention, then all my files would be generated as address-data_1.txt, address-data_2.txt,...and so on. But, where does this sequence number come from? The answer lies in the "control directory" for the particular adapter project(or scenario). In general, for every project that use the File or Ftp Adapter, a unique directory is created for book keeping purposes. And since this control directory is required to be unique, the adapter uses a digest to make sure that no two control directories are the same. For example, for my FlatStructure sample, the control information for my project would go under FMW_HOME/user_projects/domains/soainfra/fileftp/controlFiles/[DIGEST]/outbound where the value of DIGEST would differ from one project to another. If you look under this directory, you will see a file control_ob.properties and this is where the sequence number is maintained. Please note that the sequence number is maintained in binary form and you hence you might need a hex editor to view its content. You will also see another zero byte file, SEQ_nnn, but, ignore that for now. We'll get to it some other time. For now, please remember that this extra file is maintained as a backup. One of the challenges faced by the adapter runtime is to guard all writes to the control files so no two threads inadverently try to update them at the same time. And, it does so with the help of a "Mutex". For now, please remember that the mutex comes in different flavors: In-memory DB-based Coherence-based User-defined Again, we will talk about these mutexes some other time. Please note that there might be scenarios, particularly under heavy load, where the mutex might become a bottleneck. The adapter, however,  allows you to change the configuration so that the adapter sequence value comes from a database sequence or a stored procedure and in such situation, the mutex is acually by-passed and thereby resulting in better throughputs. In later releases, the behavior of the adapter would be defaulted to use a db-sequence.  The simplest way to achieve this is by switching your JNDI for the outbound JCA file to use "eis/HAFileAdapter" as shown   But, what does this do? Internally, the adapter runtime creates a sequence on the oracle database. For example, if you do a "select * from user_sequences" in your soa-infra schema, you will see a new sequence being created with name as SEQ_<GUID>__ where the GUID will differ from one project to another. However, if you want to use your own sequence, then it would require you to add a new property to your JCA file called SequenceName as shown below. Please note that you will need to create this sequence on your soainfra schema beforehand.     But, what if we use DB2 or MSSQL Server as the dehydration support? DB2 supports sequences natively but MSSQL Server does not. So, the adapter runtime uses a natively generated sequence for DB2, but, for MSSQL server, the adapter relies on a stored procedure that ships with the product. If you wish to achieve the same result for SOA Suite running DB2 as the dehydration store, simply change your connection factory JNDI name in the JCA file to eis/HAFileAdapterDB2 and for MSSQL, please use eis/HAFileAdapterMSSQL. And, if you wish to use a stored procedure other than the one that ships with the product, you will need to rely on binding properties to override the adapter behavior. Particularly, you will need to instruct the adapter that you wish to use a stored procedure as shown:       Please note that if you're using the File/Ftp Adapter in Append mode, then the adapter runtime degrades the mutex to use pessimistic locks as we don't want writers from different nodes to append to the same file at the same time.                    

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• InnoDB Compression Improvements in MySQL 5.6

  - by Inaam Rana

  MySQL 5.6 comes with significant improvements for the compression support inside InnoDB. The enhancements that we'll talk about in this piece are also a good example of community contributions. The work on these was conceived, implemented and contributed by the engineers at Facebook. Before we plunge into the details let us familiarize ourselves with some of the key concepts surrounding InnoDB compression. In InnoDB compressed pages are fixed size. Supported sizes are 1, 2, 4, 8 and 16K. The compressed page size is specified at table creation time. InnoDB uses zlib for compression. InnoDB buffer pool will attempt to cache compressed pages like normal pages. However, whenever a page is actively used by a transaction, we'll always have the uncompressed version of the page as well i.e.: we can have a page in the buffer pool in compressed only form or in a state where we have both the compressed page and uncompressed version but we'll never have a page in uncompressed only form. On-disk we'll always only have the compressed page. When both compressed and uncompressed images are present in the buffer pool they are always kept in sync i.e.: changes are applied to both atomically. Recompression happens when changes are made to the compressed data. In order to minimize recompressions InnoDB maintains a modification log within a compressed page. This is the extra space available in the page after compression and it is used to log modifications to the compressed data thus avoiding recompressions. DELETE (and ROLLBACK of DELETE) and purge can be performed without recompressing the page. This is because the delete-mark bit and the system fields DB_TRX_ID and DB_ROLL_PTR are stored in uncompressed format on the compressed page. A record can be purged by shuffling entries in the compressed page directory. This can also be useful for updates of indexed columns, because UPDATE of a key is mapped to INSERT+DELETE+purge. A compression failure happens when we attempt to recompress a page and it does not fit in the fixed size. In such case, we first try to reorganize the page and attempt to recompress and if that fails as well then we split the page into two and recompress both pages. Now lets talk about the three major improvements that we made in MySQL 5.6.Logging of Compressed Page Images:InnoDB used to log entire compressed data on the page to the redo logs when recompression happens. This was an extra safety measure to guard against the rare case where an attempt is made to do recovery using a different zlib version from the one that was used before the crash. Because recovery is a page level operation in InnoDB we have to be sure that all recompress attempts must succeed without causing a btree page split. However, writing entire compressed data images to the redo log files not only makes the operation heavy duty but can also adversely affect flushing activity. This happens because redo space is used in a circular fashion and when we generate much more than normal redo we fill up the space much more quickly and in order to reuse the redo space we have to flush the corresponding dirty pages from the buffer pool.Starting with MySQL 5.6 a new global configuration parameter innodb_log_compressed_pages. The default value is true which is same as the current behavior. If you are sure that you are not going to attempt to recover from a crash using a different version of zlib then you should set this parameter to false. This is a dynamic parameter.Compression Level:You can now set the compression level that zlib should choose to compress the data. The global parameter is innodb_compression_level - the default value is 6 (the zlib default) and allowed values are 1 to 9. Again the parameter is dynamic i.e.: you can change it on the fly.Dynamic Padding to Reduce Compression Failures:Compression failures are expensive in terms of CPU. We go through the hoops of recompress, failure, reorganize, recompress, failure and finally page split. At the same time, how often we encounter compression failure depends largely on the compressibility of the data. In MySQL 5.6, courtesy of Facebook engineers, we have an adaptive algorithm based on per-index statistics that we gather about compression operations. The idea is that if a certain index/table is experiencing too many compression failures then we should try to pack the 16K uncompressed version of the page less densely i.e.: we let some space in the 16K page go unused in an attempt that the recompression won't end up in a failure. In other words, we dynamically keep adding 'pad' to the 16K page till we get compression failures within an agreeable range. It works the other way as well, that is we'll keep removing the pad if failure rate is fairly low. To tune the padding effort two configuration variables are exposed. innodb_compression_failure_threshold_pct: default 5, range 0 - 100,dynamic, implies the percentage of compress ops to fail before we start using to padding. Value 0 has a special meaning of disabling the padding. innodb_compression_pad_pct_max: default 50, range 0 - 75, dynamic, the  maximum percentage of uncompressed data page that can be reserved as pad.

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• 3 Trends for SMBs around Social, Mobile, and Sensor

  - by Socially_Aware_Enterprise

  While I often am talking to big companies or discussing enterprise solutions. There are times when individuals ask me about Small or Medium sized business trends.  Interestingly,  the Enterprise Social, Mobile, and Sensor initiatives I regularly discuss are in fact related to even the Mom and Pop storefront. The eco-system of new service players in the Social-Mobile-Sensor space generally emerge developing partnerships with enterprises as they develop and bring economy to scale to their services for the larger market. And of course Oracle has an entire division dedicated for delivering products and support to help emerging companies compete without the need to open an industrial strength credit line.. So here are some trends that we are helping large enterprises to deploy today, but small and medium businesses should be able to take advantage of by the end of this year and starting into 2015. 1) The typical small business is generally "Localized". But the ability to be "Hyper-Localized" will come as location based services become ubiquitous. Many small businesses have one or several storefronts and theirs are typically within a single regional economic footprint. While the internet provides global reach, it will be the businesses that invest in social, mobile and local that will win in the end.  Of course I am a huge SoMoLo evangelist. The SMBs' content and targeting with platforms for Geo-Fencing, Geo-Conquesting and Path-Matching to HHI are all going to be accessible to them, if not for Mobile Apps, then via Mobile messaging in Social Networks that offer it.. Expect to be able to target FaceBook messaging not by city, but by store or mall… This makes being able to be "Hyper-Local" even more important. And with new proximity services coming online more than ever before, SMBs will operate and service customers with pinpoint accuracy right down to where they stand in an aisle. Geo-Conquesting will be huge for small players to place ads when customers pass through competitors regions. Car Dealers are doing this now.. But also of course iBeacons are now very cheap and getting easier to put in retail stores. The ability for sales to happen anywhere in the store via a mobile phone or tablet is huge, as it will give the small shop the flexibility to not have to "Guard the Register" as more or most transactions will be digital. Thus, M-Commerce and T-Commerce will change the job of cashier dramatically.. 2) Intra-Brand Advocacy, the idea now is that rather than just depend on your trusty social media manager and his team, you are going to push more and more individuals with expertise inside the organization to help manage, reach-out, and utilize social channels to manage the incoming questions and answers customers need. While for years CRM was the tool of the enterprise, today CRMs enable this now "Salesforce et al" capability to trickle throughout the company. This gives greater pressure to organize roles, but also flatten out the organization. Internal collaboration around topics and customer needs is going to be the key for SMBs to finally get serious about customer experiences. Their customers are online and in social networks. This includes not just B2C SMBs but also B2B companies as well. Don't believe me? To find the players just use hashtag #SocialSelling and you will see… 3) The Visual Networks will begin to move from Content Aggregators to Content Collaboration platforms, which means Pinterest, Instagram, Vine, & others will begin to move to add more features brands want, first marketing platforms, rather than unique brand partnerships as they do today, but this will open ways for SMBs to engage with clear brand messaging and metrics. Eventually providing more "Collaboration" between Brand and Consumer.. Don't think for a minute Facebook bought Oculus Rift so you could see your timeline in 3-D. The Social Networks I advise customers to invest in are ones that are audio and visual intrinsically. Players from SoundCloud to Pinterest are deploying ways for brands to harness their interactive visual or audio based social networks to sell ad units aka brand messaging. While the Social Media revolution is going on, the emphasis was on the social, today it more and more about the media in social, that enterprises soon small and medium businesses will be connected to. 

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• Computer Networks UNISA - Chap 14 &ndash; Insuring Integrity &amp; Availability

  - by MarkPearl

  After reading this section you should be able to Identify the characteristics of a network that keep data safe from loss or damage Protect an enterprise-wide network from viruses Explain network and system level fault tolerance techniques Discuss issues related to network backup and recovery strategies Describe the components of a useful disaster recovery plan and the options for disaster contingencies What are integrity and availability? Integrity – the soundness of a networks programs, data, services, devices, and connections Availability – How consistently and reliably a file or system can be accessed by authorized personnel A number of phenomena can compromise both integrity and availability including… security breaches natural disasters malicious intruders power flaws human error users etc Although you cannot predict every type of vulnerability, you can take measures to guard against the most damaging events. The following are some guidelines… Allow only network administrators to create or modify NOS and application system users. Monitor the network for unauthorized access or changes Record authorized system changes in a change management system’ Install redundant components Perform regular health checks on the network Check system performance, error logs, and the system log book regularly Keep backups Implement and enforce security and disaster recovery policies These are just some of the basics… Malware Malware refers to any program or piece of code designed to intrude upon or harm a system or its resources. Types of Malware… Boot sector viruses Macro viruses File infector viruses Worms Trojan Horse Network Viruses Bots Malware characteristics Some common characteristics of Malware include… Encryption Stealth Polymorphism Time dependence Malware Protection There are various tools available to protect you from malware called anti-malware software. These monitor your system for indications that a program is performing potential malware operations. A number of techniques are used to detect malware including… Signature Scanning Integrity Checking Monitoring unexpected file changes or virus like behaviours It is important to decide where anti-malware tools will be installed and find a balance between performance and protection. There are several general purpose malware policies that can be implemented to protect your network including… Every compute in an organization should be equipped with malware detection and cleaning software that regularly runs Users should not be allowed to alter or disable the anti-malware software Users should know what to do in case the anti-malware program detects a malware virus Users should be prohibited from installing any unauthorized software on their systems System wide alerts should be issued to network users notifying them if a serious malware virus has been detected. Fault Tolerance Besides guarding against malware, another key factor in maintaining the availability and integrity of data is fault tolerance. Fault tolerance is the ability for a system to continue performing despite an unexpected hardware or software malfunction. Fault tolerance can be realized in varying degrees, the optimal level of fault tolerance for a system depends on how critical its services and files are to productivity. Generally the more fault tolerant the system, the more expensive it is. The following describe some of the areas that need to be considered for fault tolerance. Environment (Temperature and humidity) Power Topology and Connectivity Servers Storage Power Typical power flaws include Surges – a brief increase in voltage due to lightening strikes, solar flares or some idiot at City Power Noise – Fluctuation in voltage levels caused by other devices on the network or electromagnetic interference Brownout – A sag in voltage for just a moment Blackout – A complete power loss The are various alternate power sources to consider including UPS’s and Generators. UPS’s are found in two categories… Standby UPS – provides continuous power when mains goes down (brief period of switching over) Online UPS – is online all the time and the device receives power from the UPS all the time (the UPS is charged continuously) Servers There are various techniques for fault tolerance with servers. Server mirroring is an option where one device or component duplicates the activities of another. It is generally an expensive process. Clustering is a fault tolerance technique that links multiple servers together to appear as a single server. They share processing and storage responsibilities and if one unit in the cluster goes down, another unit can be brought in to replace it. Storage There are various techniques available including the following… RAID Arrays NAS (Storage (Network Attached Storage) SANs (Storage Area Networks) Data Backup A backup is a copy of data or program files created for archiving or safekeeping. Many different options for backups exist with various media including… These vary in cost and speed. Optical Media Tape Backup External Disk Drives Network Backups Backup Strategy After selecting the appropriate tool for performing your servers backup, devise a backup strategy to guide you through performing reliable backups that provide maximum data protection. Questions that should be answered include… What data must be backed up At what time of day or night will the backups occur How will you verify the accuracy of the backups Where and for how long will backup media be stored Who will take responsibility for ensuring that backups occurred How long will you save backups Where will backup and recovery documentation be stored Different backup methods provide varying levels of certainty and corresponding labour cost. There are also different ways to determine which files should be backed up including… Full backup – all data on all servers is copied to storage media Incremental backup – Only data that has changed since the last full or incremental backup is copied to a storage medium Differential backup – Only data that has changed since the last backup is coped to a storage medium Disaster Recovery Disaster recovery is the process of restoring your critical functionality and data after an enterprise wide outage has occurred. A disaster recovery plan is for extreme scenarios (i.e. fire, line fault, etc). A cold site is a place were the computers, devices, and connectivity necessary to rebuild a network exist but they are not appropriately configured. A warm site is a place where the computers, devices, and connectivity necessary to rebuild a network exists with some appropriately configured devices. A hot site is a place where the computers, devices, and connectivity necessary to rebuild a network exists and all are appropriately configured.

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• JPRT: A Build & Test System

  - by kto

  DRAFT A while back I did a little blogging on a system called JPRT, the hardware used and a summary on my java.net weblog. This is an update on the JPRT system. JPRT ("JDK Putback Reliablity Testing", but ignore what the letters stand for, I change what they mean every day, just to annoy people :\^) is a build and test system for the JDK, or any source base that has been configured for JPRT. As I mentioned in the above blog, JPRT is a major modification to a system called PRT that the HotSpot VM development team has been using for many years, very successfully I might add. Keeping the source base always buildable and reliable is the first step in the 12 steps of dealing with your product quality... or was the 12 steps from Alcoholics Anonymous... oh well, anyway, it's the first of many steps. ;\^) Internally when we make changes to any part of the JDK, there are certain procedures we are required to perform prior to any putback or commit of the changes. The procedures often vary from team to team, depending on many factors, such as whether native code is changed, or if the change could impact other areas of the JDK. But a common requirement is a verification that the source base with the changes (and merged with the very latest source base) will build on many of not all 8 platforms, and a full 'from scratch' build, not an incremental build, which can hide full build problems. The testing needed varies, depending on what has been changed. Anyone that was worked on a project where multiple engineers or groups are submitting changes to a shared source base knows how disruptive a 'bad commit' can be on everyone. How many times have you heard: "So And So made a bunch of changes and now I can't build!". But multiply the number of platforms by 8, and make all the platforms old and antiquated OS versions with bizarre system setup requirements and you have a pretty complicated situation (see http://download.java.net/jdk6/docs/build/README-builds.html). We don't tolerate bad commits, but our enforcement is somewhat lacking, usually it's an 'after the fact' correction. Luckily the Source Code Management system we use (another antique called TeamWare) allows for a tree of repositories and 'bad commits' are usually isolated to a small team. Punishment to date has been pretty drastic, the Queen of Hearts in 'Alice in Wonderland' said 'Off With Their Heads', well trust me, you don't want to be the engineer doing a 'bad commit' to the JDK. With JPRT, hopefully this will become a thing of the past, not that we have had many 'bad commits' to the master source base, in general the teams doing the integrations know how important their jobs are and they rarely make 'bad commits'. So for these JDK integrators, maybe what JPRT does is keep them from chewing their finger nails at night. ;\^) Over the years each of the teams have accumulated sets of machines they use for building, or they use some of the shared machines available to all of us. But the hunt for build machines is just part of the job, or has been. And although the issues with consistency of the build machines hasn't been a horrible problem, often you never know if the Solaris build machine you are using has all the right patches, or if the Linux machine has the right service pack, or if the Windows machine has it's latest updates. Hopefully the JPRT system can solve this problem. When we ship the binary JDK bits, it is SO very important that the build machines are correct, and we know how difficult it is to get them setup. Sure, if you need to debug a JDK problem that only shows up on Windows XP or Solaris 9, you'll still need to hunt down a machine, but not as a regular everyday occurance. I'm a big fan of a regular nightly build and test system, constantly verifying that a source base builds and tests out. There are many examples of automated build/tests, some that trigger on any change to the source base, some that just run every night. Some provide a protection gateway to the 'golden' source base which only gets changes that the nightly process has verified are good. The JPRT (and PRT) system is meant to guard the source base before anything is sent to it, guarding all source bases from the evil developer, well maybe 'evil' isn't the right word, I haven't met many 'evil' developers, more like 'error prone' developers. ;\^) Humm, come to think about it, I may be one from time to time. :\^{ But the point is that by spreading the build up over a set of machines, and getting the turnaround down to under an hour, it becomes realistic to completely build on all platforms and test it, on every putback. We have the technology, we can build and rebuild and rebuild, and it will be better than it was before, ha ha... Anybody remember the Six Million Dollar Man? Man, I gotta get out more often.. Anyway, now the nightly build and test can become a 'fetch the latest JPRT build bits' and start extensive testing (the testing not done by JPRT, or the platforms not tested by JPRT). Is it Open Source? No, not yet. Would you like to be? Let me know. Or is it more important that you have the ability to use such a system for JDK changes? So enough blabbering on about this JPRT system, tell me what you think. And let me know if you want to hear more about it or not. Stay tuned for the next episode, same Bloody Bat time, same Bloody Bat channel. ;\^) -kto

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• Cloud to On-Premise Connectivity Patterns

  - by Rajesh Raheja

  Do you have a requirement to convert an Opportunity in Salesforce.com to an Order/Quote in Oracle E-Business Suite? Or maybe you want the creation of an Oracle RightNow Incident to trigger an on-premise Oracle E-Business Suite Service Request creation for RMA and Field Scheduling? If so, read on. In a previous blog post, I discussed integrating TO cloud applications, however the use cases above are the reverse i.e. receiving data FROM cloud applications (SaaS) TO on-premise applications/databases that sit behind a firewall. Oracle SOA Suite is assumed to be on-premise with with Oracle Service Bus as the mediation and virtualization layer. The main considerations for the patterns are are security i.e. shielding enterprise resources; and scalability i.e. minimizing firewall latency. Let me use an analogy to help visualize the patterns: the on-premise system is your home - with your most valuable possessions - and the SaaS app is your favorite on-line store which regularly ships (inbound calls) various types of parcels/items (message types/service operations). You need the items at home (on-premise) but want to safe guard against misguided elements of society (internet threats) who may masquerade as postal workers and vandalize property (denial of service?). Let's look at the patterns. Pattern: Pull from Cloud The on-premise system polls from the SaaS apps and picks up the message instead of having it delivered. This may be done using Oracle RightNow Object Query Language or SOAP APIs. This is particularly suited for certain integration approaches wherein messages are trickling in, can be centralized and batched e.g. retrieving event notifications on an hourly schedule from the Oracle Messaging Service. To compare this pattern with the home analogy, you are avoiding any deliveries to your home and instead go to the post office/UPS/Fedex store to pick up your parcel. Every time. Pros: On-premise assets not exposed to the Internet, firewall issues avoided by only initiating outbound connections Cons: Polling mechanisms may affect performance, may not satisfy near real-time requirements Pattern: Open Firewall Ports The on-premise system exposes the web services that needs to be invoked by the cloud application. This requires opening up firewall ports, routing calls to the appropriate internal services behind the firewall. Fusion Applications uses this pattern, and auto-provisions the services on the various virtual hosts to secure the topology. This works well for service integration, but may not suffice for large volume data integration. Using the home analogy, you have now decided to receive parcels instead of going to the post office every time. A door mail slot cut out allows the postman can drop small parcels, but there is still concern about cutting new holes for larger packages. Pros: optimal pattern for near real-time needs, simpler administration once the service is provisioned Cons: Needs firewall ports to be opened up for new services, may not suffice for batch integration requiring direct database access Pattern: Virtual Private Networking The on-premise network is "extended" to the cloud (or an intermediary on-demand / managed service offering) using Virtual Private Networking (VPN) so that messages are delivered to the on-premise system in a trusted channel. Using the home analogy, you entrust a set of keys with a neighbor or property manager who receives the packages, and then drops it inside your home. Pros: Individual firewall ports don't need to be opened, more suited for high scalability needs, can support large volume data integration, easier management of one connection vs a multitude of open ports Cons: VPN setup, specific hardware support, requires cloud provider to support virtual private computing Pattern: Reverse Proxy / API Gateway The on-premise system uses a reverse proxy "API gateway" software on the DMZ to receive messages. The reverse proxy can be implemented using various mechanisms e.g. Oracle API Gateway provides firewall and proxy services along with comprehensive security, auditing, throttling benefits. If a firewall already exists, then Oracle Service Bus or Oracle HTTP Server virtual hosts can provide reverse proxy implementations on the DMZ. Custom built implementations are also possible if specific functionality (such as message store-n-forward) is needed. In the home analogy, this pattern sits in between cutting mail slots and handing over keys. Instead, you install (and maintain) a mailbox in your home premises outside your door. The post office delivers the parcels in your mailbox, from where you can securely retrieve it. Pros: Very secure, very flexible Cons: Introduces a new software component, needs DMZ deployment and management Pattern: On-Premise Agent (Tunneling) A light weight "agent" software sits behind the firewall and initiates the communication with the cloud, thereby avoiding firewall issues. It then maintains a bi-directional connection either with pull or push based approaches using (or abusing, depending on your viewpoint) the HTTP protocol. Programming protocols such as Comet, WebSockets, HTTP CONNECT, HTTP SSH Tunneling etc. are possible implementation options. In the home analogy, a resident receives the parcel from the postal worker by opening the door, however you still take precautions with chain locks and package inspections. Pros: Light weight software, IT doesn't need to setup anything Cons: May bypass critical firewall checks e.g. virus scans, separate software download, proliferation of non-IT managed software Conclusion The patterns above are some of the most commonly encountered ones for cloud to on-premise integration. Selecting the right pattern for your project involves looking at your scalability needs, security restrictions, sync vs asynchronous implementation, near real-time vs batch expectations, cloud provider capabilities, budget, and more. In some cases, the basic "Pull from Cloud" may be acceptable, whereas in others, an extensive VPN topology may be well justified. For more details on the Oracle cloud integration strategy, download this white paper.

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• Cloud to On-Premise Connectivity Patterns

  - by Rajesh Raheja

  Do you have a requirement to convert an Opportunity in Salesforce.com to an Order/Quote in Oracle E-Business Suite? Or maybe you want the creation of an Oracle RightNow Incident to trigger an on-premise Oracle E-Business Suite Service Request creation for RMA and Field Scheduling? If so, read on. In a previous blog post, I discussed integrating TO cloud applications, however the use cases above are the reverse i.e. receiving data FROM cloud applications (SaaS) TO on-premise applications/databases that sit behind a firewall. Oracle SOA Suite is assumed to be on-premise with with Oracle Service Bus as the mediation and virtualization layer. The main considerations for the patterns are are security i.e. shielding enterprise resources; and scalability i.e. minimizing firewall latency. Let me use an analogy to help visualize the patterns: the on-premise system is your home - with your most valuable possessions - and the SaaS app is your favorite on-line store which regularly ships (inbound calls) various types of parcels/items (message types/service operations). You need the items at home (on-premise) but want to safe guard against misguided elements of society (internet threats) who may masquerade as postal workers and vandalize property (denial of service?). Let's look at the patterns. Pattern: Pull from Cloud The on-premise system polls from the SaaS apps and picks up the message instead of having it delivered. This may be done using Oracle RightNow Object Query Language or SOAP APIs. This is particularly suited for certain integration approaches wherein messages are trickling in, can be centralized and batched e.g. retrieving event notifications on an hourly schedule from the Oracle Messaging Service. To compare this pattern with the home analogy, you are avoiding any deliveries to your home and instead go to the post office/UPS/Fedex store to pick up your parcel. Every time. Pros: On-premise assets not exposed to the Internet, firewall issues avoided by only initiating outbound connections Cons: Polling mechanisms may affect performance, may not satisfy near real-time requirements Pattern: Open Firewall Ports The on-premise system exposes the web services that needs to be invoked by the cloud application. This requires opening up firewall ports, routing calls to the appropriate internal services behind the firewall. Fusion Applications uses this pattern, and auto-provisions the services on the various virtual hosts to secure the topology. This works well for service integration, but may not suffice for large volume data integration. Using the home analogy, you have now decided to receive parcels instead of going to the post office every time. A door mail slot cut out allows the postman can drop small parcels, but there is still concern about cutting new holes for larger packages. Pros: optimal pattern for near real-time needs, simpler administration once the service is provisioned Cons: Needs firewall ports to be opened up for new services, may not suffice for batch integration requiring direct database access Pattern: Virtual Private Networking The on-premise network is "extended" to the cloud (or an intermediary on-demand / managed service offering) using Virtual Private Networking (VPN) so that messages are delivered to the on-premise system in a trusted channel. Using the home analogy, you entrust a set of keys with a neighbor or property manager who receives the packages, and then drops it inside your home. Pros: Individual firewall ports don't need to be opened, more suited for high scalability needs, can support large volume data integration, easier management of one connection vs a multitude of open ports Cons: VPN setup, specific hardware support, requires cloud provider to support virtual private computing Pattern: Reverse Proxy / API Gateway The on-premise system uses a reverse proxy "API gateway" software on the DMZ to receive messages. The reverse proxy can be implemented using various mechanisms e.g. Oracle API Gateway provides firewall and proxy services along with comprehensive security, auditing, throttling benefits. If a firewall already exists, then Oracle Service Bus or Oracle HTTP Server virtual hosts can provide reverse proxy implementations on the DMZ. Custom built implementations are also possible if specific functionality (such as message store-n-forward) is needed. In the home analogy, this pattern sits in between cutting mail slots and handing over keys. Instead, you install (and maintain) a mailbox in your home premises outside your door. The post office delivers the parcels in your mailbox, from where you can securely retrieve it. Pros: Very secure, very flexible Cons: Introduces a new software component, needs DMZ deployment and management Pattern: On-Premise Agent (Tunneling) A light weight "agent" software sits behind the firewall and initiates the communication with the cloud, thereby avoiding firewall issues. It then maintains a bi-directional connection either with pull or push based approaches using (or abusing, depending on your viewpoint) the HTTP protocol. Programming protocols such as Comet, WebSockets, HTTP CONNECT, HTTP SSH Tunneling etc. are possible implementation options. In the home analogy, a resident receives the parcel from the postal worker by opening the door, however you still take precautions with chain locks and package inspections. Pros: Light weight software, IT doesn't need to setup anything Cons: May bypass critical firewall checks e.g. virus scans, separate software download, proliferation of non-IT managed software Conclusion The patterns above are some of the most commonly encountered ones for cloud to on-premise integration. Selecting the right pattern for your project involves looking at your scalability needs, security restrictions, sync vs asynchronous implementation, near real-time vs batch expectations, cloud provider capabilities, budget, and more. In some cases, the basic "Pull from Cloud" may be acceptable, whereas in others, an extensive VPN topology may be well justified. For more details on the Oracle cloud integration strategy, download this white paper.

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• Plagued by multithreaded bugs

  - by koncurrency

  On my new team that I manage, the majority of our code is platform, TCP socket, and http networking code. All C++. Most of it originated from other developers that have left the team. The current developers on the team are very smart, but mostly junior in terms of experience. Our biggest problem: multi-threaded concurrency bugs. Most of our class libraries are written to be asynchronous by use of some thread pool classes. Methods on the class libraries often enqueue long running taks onto the thread pool from one thread and then the callback methods of that class get invoked on a different thread. As a result, we have a lot of edge case bugs involving incorrect threading assumptions. This results in subtle bugs that go beyond just having critical sections and locks to guard against concurrency issues. What makes these problems even harder is that the attempts to fix are often incorrect. Some mistakes I've observed the team attempting (or within the legacy code itself) includes something like the following: Common mistake #1 - Fixing concurrency issue by just put a lock around the shared data, but forgetting about what happens when methods don't get called in an expected order. Here's a very simple example: void Foo::OnHttpRequestComplete(statuscode status) { m_pBar->DoSomethingImportant(status); } void Foo::Shutdown() { m_pBar->Cleanup(); delete m_pBar; m_pBar=nullptr; } So now we have a bug in which Shutdown could get called while OnHttpNetworkRequestComplete is occuring on. A tester finds the bug, captures the crash dump, and assigns the bug to a developer. He in turn fixes the bug like this. void Foo::OnHttpRequestComplete(statuscode status) { AutoLock lock(m_cs); m_pBar->DoSomethingImportant(status); } void Foo::Shutdown() { AutoLock lock(m_cs); m_pBar->Cleanup(); delete m_pBar; m_pBar=nullptr; } The above fix looks good until you realize there's an even more subtle edge case. What happens if Shutdown gets called before OnHttpRequestComplete gets called back? The real world examples my team has are even more complex, and the edge cases are even harder to spot during the code review process. Common Mistake #2 - fixing deadlock issues by blindly exiting the lock, wait for the other thread to finish, then re-enter the lock - but without handling the case that the object just got updated by the other thread! Common Mistake #3 - Even though the objects are reference counted, the shutdown sequence "releases" it's pointer. But forgets to wait for the thread that is still running to release it's instance. As such, components are shutdown cleanly, then spurious or late callbacks are invoked on an object in an state not expecting any more calls. There are other edge cases, but the bottom line is this: Multithreaded programming is just plain hard, even for smart people. As I catch these mistakes, I spend time discussing the errors with each developer on developing a more appropriate fix. But I suspect they are often confused on how to solve each issue because of the enormous amount of legacy code that the "right" fix will involve touching. We're going to be shipping soon, and I'm sure the patches we're applying will hold for the upcoming release. Afterwards, we're going to have some time to improve the code base and refactor where needed. We won't have time to just re-write everything. And the majority of the code isn't all that bad. But I'm looking to refactor code such that threading issues can be avoided altogether. One approach I am considering is this. For each significant platform feature, have a dedicated single thread where all events and network callbacks get marshalled onto. Similar to COM apartment threading in Windows with use of a message loop. Long blocking operations could still get dispatched to a work pool thread, but the completion callback is invoked on on the component's thread. Components could possibly even share the same thread. Then all the class libraries running inside the thread can be written under the assumption of a single threaded world. Before I go down that path, I am also very interested if there are other standard techniques or design patterns for dealing with multithreaded issues. And I have to emphasize - something beyond a book that describes the basics of mutexes and semaphores. What do you think? I am also interested in any other approaches to take towards a refactoring process. Including any of the following: Literature or papers on design patterns around threads. Something beyond an introduction to mutexes and semaphores. We don't need massive parallelism either, just ways to design an object model so as to handle asynchronous events from other threads correctly. Ways to diagram the threading of various components, so that it will be easy to study and evolve solutions for. (That is, a UML equivalent for discussing threads across objects and classes) Educating your development team on the issues with multithreaded code. What would you do?

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• EXC_BAD_ACCESS error on a UITableView with ARC?

  - by Arnaud Drizard

  I am building a simple app with a custom bar tab which loads the content of the ViewController from a UITableView located in another ViewController. However, every time I try to scroll on the tableview, I get an exc_bad_access error. I enabled NSzombies and guard malloc to get more info on the issue. In the console I get: "message sent to deallocated instance 0x19182f20" and after profiling I get: # Address Category Event Type RefCt Timestamp Size Responsible Library Responsible Caller 56 0x19182f20 FirstTabBarViewController Zombie -1 00:16.613.309 0 UIKit -[UIScrollView(UIScrollViewInternal) _scrollViewWillBeginDragging] Here is a bit of the code of the ViewController in which the error occurs: .h file: #import <UIKit/UIKit.h> #import "DataController.h" @interface FirstTabBarViewController : UIViewController <UITableViewDelegate, UITableViewDataSource> { IBOutlet UITableView* tabBarTable; } @property (strong, nonatomic) IBOutlet UIView *mainView; @property (strong, nonatomic) IBOutlet UITableView *tabBarTable; @property (nonatomic, strong) DataController *messageDataController; @end .m file: #import "FirstTabBarViewController.h" #import "DataController.h" @interface FirstTabBarViewController () @end @implementation FirstTabBarViewController @synthesize tabBarTable=_tabBarTable; - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; if (self) { // Custom initialization } return self; } - (void)viewDidLoad { [super viewDidLoad]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } - (void)awakeFromNib { [super awakeFromNib]; self.messageDataController=[[DataController alloc] init]; } - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1; } - (NSInteger) tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{ return [self.messageDataController countOfList]; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"mainCell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil){ cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier]; }; NSString *expenseAtIndex = [self.messageDataController objectInListAtIndex:indexPath.row]; [[cell textLabel] setText:expenseAtIndex]; return cell; } - (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath { // Return NO if you do not want the specified item to be editable. return NO; } @end This FirstTabBarViewController is loaded in the MainViewController with the following custom segue: #import "customTabBarSegue.h" #import "MainViewController.h" @implementation customTabBarSegue -(void) perform { MainViewController *src= (MainViewController *) [self sourceViewController]; UIViewController *dst=(UIViewController *)[self destinationViewController]; for (UIView *view in src.placeholderView.subviews){ [view removeFromSuperview]; } src.currentViewController =dst; [src.placeholderView addSubview:dst.view]; } @end The Datacontroller class is just a simple NSMutableArray containing strings. I am using ARC so I don't understand where the memory management error comes from. Does anybody have a clue? Any help much appreciated ;) Thanks!!

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• Which functions in the C standard library commonly encourage bad practice?

  - by Ninefingers

  Hello all, This is inspired by this question and the comments on one particular answer in that I learnt that strncpy is not a very safe string handling function in C and that it pads zeros, until it reaches n, something I was unaware of. Specifically, to quote R.. strncpy does not null-terminate, and does null-pad the whole remainder of the destination buffer, which is a huge waste of time. You can work around the former by adding your own null padding, but not the latter. It was never intended for use as a "safe string handling" function, but for working with fixed-size fields in Unix directory tables and database files. snprintf(dest, n, "%s", src) is the only correct "safe strcpy" in standard C, but it's likely to be a lot slower. By the way, truncation in itself can be a major bug and in some cases might lead to privilege elevation or DoS, so throwing "safe" string functions that truncate their output at a problem is not a way to make it "safe" or "secure". Instead, you should ensure that the destination buffer is the right size and simply use strcpy (or better yet, memcpy if you already know the source string length). And from Jonathan Leffler Note that strncat() is even more confusing in its interface than strncpy() - what exactly is that length argument, again? It isn't what you'd expect based on what you supply strncpy() etc - so it is more error prone even than strncpy(). For copying strings around, I'm increasingly of the opinion that there is a strong argument that you only need memmove() because you always know all the sizes ahead of time and make sure there's enough space ahead of time. Use memmove() in preference to any of strcpy(), strcat(), strncpy(), strncat(), memcpy(). So, I'm clearly a little rusty on the C standard library. Therefore, I'd like to pose the question: What C standard library functions are used inappropriately/in ways that may cause/lead to security problems/code defects/inefficiencies? In the interests of objectivity, I have a number of criteria for an answer: Please, if you can, cite design reasons behind the function in question i.e. its intended purpose. Please highlight the misuse to which the code is currently put. Please state why that misuse may lead towards a problem. I know that should be obvious but it prevents soft answers. Please avoid: Debates over naming conventions of functions (except where this unequivocably causes confusion). "I prefer x over y" - preference is ok, we all have them but I'm interested in actual unexpected side effects and how to guard against them. As this is likely to be considered subjective and has no definite answer I'm flagging for community wiki straight away. I am also working as per C99.

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• boost multi_index_container and erase performance

  - by rjoshi

  I have a boost multi_index_container declared as below which is indexed by hash_unique id(unsigned long) and hash_non_unique transaction id(long). Insertion and retrieval of elements is fast but when I delete elements, it is much slower. I was expecting it to be constant time as key is hashed. e.g To erase elements from container for 10,000 elements, it takes around 2.53927016 seconds for 15,000 elements, it takes around 7.137100068 seconds for 20,000 elements, it takes around 21.391720757 seconds Is it something I am missing or is it expected behavior? class Session { public: Session() { //increment unique id static unsigned long counter = 0; boost::mutex::scoped_lock guard(mx); counter++; m_nId = counter; } unsigned long GetId() { return m_nId; } long GetTransactionHandle(){ return m_nTransactionHandle; } .... private: unsigned long m_nId; long m_nTransactionHandle; boost::mutext mx; .... }; typedef multi_index_container< Session*, indexed_by< hashed_unique< mem_fun<Session,unsigned long,&Session::GetId> >, hashed_non_unique< mem_fun<Session,unsigned long,&Session::GetTransactionHandle> > > //end indexed_by > SessionContainer; typedef SessionContainer::nth_index<0>::type SessionById; int main() { ... SessionContainer container; SessionById *pSessionIdView = &get<0>(container); unsigned counter = atoi(argv[1]); vector<Session*> vSes(counter); //insert for(unsigned i = 0; i < counter; i++) { Session *pSes = new Session(); container.insert(pSes); vSes.push_back(pSes); } timespec ts; lock_settime(CLOCK_PROCESS_CPUTIME_ID, &ts); //erase for(unsigned i = 0; i < counter; i++) { pSessionIdView->erase(vSes[i]->getId()); delete vSes[i]; } lock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts); std::cout << "Total time taken for erase:" << ts.tv_sec << "." << ts.tv_nsec << "\n"; return (EXIST_SUCCESS); }

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• Instagram API and Zend/Loader.php

  - by Jaemin Kim

  I want to use Instagram API and I found this code. <html> <head></head> <body> <h1>Popular on Instagram</h1> <?php // load Zend classes require_once 'Zend/Loader.php'; Zend_Loader::loadClass('Zend_Http_Client'); // define consumer key and secret // available from Instagram API console $CLIENT_ID = 'YOUR-CLIENT-ID'; $CLIENT_SECRET = 'YOUR-CLIENT-SECRET'; try { // initialize client $client = new Zend_Http_Client('https://api.instagram.com/v1/media/popular'); $client->setParameterGet('client_id', $CLIENT_ID); // get popular images // transmit request and decode response $response = $client->request(); $result = json_decode($response->getBody()); // display images $data = $result->data; if (count($data) > 0) { echo '<ul>'; foreach ($data as $item) { echo '<li style="display: inline-block; padding: 25px"><a href="' . $item->link . '"><img src="' . $item->images->thumbnail->url . '" /></a> <br/>'; echo 'By: <em>' . $item->user->username . '</em> <br/>'; echo 'Date: ' . date ('d M Y h:i:s', $item->created_time) . '<br/>'; echo $item->comments->count . ' comment(s). ' . $item->likes->count . ' likes. </li>'; } echo '</ul>'; } } catch (Exception $e) { echo 'ERROR: ' . $e->getMessage() . print_r($client); exit; } ?> </body> </html> In here, I found Zender/Load.php, and I've never heard about that. Is it okay to go http://www.zend.com/en/products/guard/downloads here, and download Zend for linux?? And for another question, is this code available to use Instagram API?? For last, could you let me know that is there any simple code to use Instagram API? Thank you.

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• Haskell Add Function Return to List Until Certain Length

  - by kienjakenobi

  I want to write a function which takes a list and constructs a subset of that list of a certain length based on the output of a function. If I were simply interested in the first 50 elements of the sorted list xs, then I would use fst (splitAt 50 (sort xs)). However, the problem is that elements in my list rely on other elements in the same list. If I choose element p, then I MUST also choose elements q and r, even if they are not in the first 50 elements of my list. I am using a function finderFunc which takes an element a from the list xs and returns a list with the element a and all of its required elements. finderFunc works fine. Now, the challenge is to write a function which builds a list whose total length is 50 based on multiple outputs of finderFunc. Here is my attempt at this: finish :: [a] -> [a] -> [a] --This is the base case, which adds nothing to the final list finish [] fs = [] --The function is recursive, so the fs variable is necessary so that finish -- can forward the incomplete list to itself. finish ps fs -- If the final list fs is too small, add elements to it | length fs < 50 && length (fs ++ newrs) <= 50 = fs ++ finish newps newrs -- If the length is met, then add nothing to the list and quit | length fs >= 50 = finish [] fs -- These guard statements are currently lacking, not the main problem | otherwise = finish [] fs where --Sort the candidate list sortedps = sort ps --(finderFunc a) returns a list of type [a] containing a and all the -- elements which are required to go with it. This is the interesting -- bit. rs is also a subset of the candidate list ps. rs = finderFunc (head sortedps) --Remove those elements which are already in the final list, because -- there can be overlap newrs = filter (`notElem` fs) rs --Remove the elements we will add to the list from the new list -- of candidates newps = filter (`notElem` rs) ps I realize that the above if statements will, in some cases, not give me a list of exactly 50 elements. This is not the main problem, right now. The problem is that my function finish does not work at all as I would expect it to. Not only does it produce duplicate elements in the output list, but it sometimes goes far above the total number of elements I want to have in the list. The way this is written, I usually call it with an empty list, such as: finish xs [], so that the list it builds on starts as an empty list.

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• i cant ping to my DMZ zone from the local inside PC

  - by Big Denzel

  HI everybody. Can anyone please help me on the following issue. I got a Cisco Asa 5520 configured at my network. I cant ping to my DMZ interface from a local inside network PC. so the only way a ping the DMZ is right from the Cisco ASA firewall, there i can pint to all 3 interfaces, Inside, Outside and DMZ,,,, But no PC from the Inside Network can access the DMZ. Can please any one help? I thank you all in advance Bellow is my Cisco ASA 5520 Firewall show run; ASA-FW# sh run : Saved : ASA Version 7.0(8) ! hostname ASA-FW enable password encrypted passwd encrypted names dns-guard ! interface GigabitEthernet0/0 description "Link-To-GW-Router" nameif outside security-level 0 ip address 41.223.156.109 255.255.255.248 ! interface GigabitEthernet0/1 description "Link-To-Local-LAN" nameif inside security-level 100 ip address 10.1.4.1 255.255.252.0 ! interface GigabitEthernet0/2 description "Link-To-DMZ" nameif dmz security-level 50 ip address 172.16.16.1 255.255.255.0 ! interface GigabitEthernet0/3 shutdown no nameif no security-level no ip address ! interface Management0/0 description "Local-Management-Interface" no nameif no security-level ip address 192.168.192.1 255.255.255.0 ! ftp mode passive access-list OUT-TO-DMZ extended permit tcp any host 41.223.156.107 eq smtp access-list OUT-TO-DMZ extended permit tcp any host 41.223.156.106 eq www access-list OUT-TO-DMZ extended permit icmp any any log access-list OUT-TO-DMZ extended deny ip any any access-list inside extended permit tcp any any eq pop3 access-list inside extended permit tcp any any eq smtp access-list inside extended permit tcp any any eq ssh access-list inside extended permit tcp any any eq telnet access-list inside extended permit tcp any any eq https access-list inside extended permit udp any any eq domain access-list inside extended permit tcp any any eq domain access-list inside extended permit tcp any any eq www access-list inside extended permit ip any any access-list inside extended permit icmp any any access-list dmz extended permit ip any any access-list dmz extended permit icmp any any access-list cap extended permit ip 10.1.4.0 255.255.252.0 172.16.16.0 255.255.25 5.0 access-list cap extended permit ip 172.16.16.0 255.255.255.0 10.1.4.0 255.255.25 2.0 no pager logging enable logging buffer-size 5000 logging monitor warnings logging trap warnings mtu outside 1500 mtu inside 1500 mtu dmz 1500 no failover asdm image disk0:/asdm-508.bin no asdm history enable arp timeout 14400 global (outside) 1 interface nat (inside) 1 0.0.0.0 0.0.0.0 static (dmz,outside) tcp 41.223.156.106 www 172.16.16.80 www netmask 255.255.255 .255 static (dmz,outside) tcp 41.223.156.107 smtp 172.16.16.25 smtp netmask 255.255.2 55.255 static (inside,dmz) 10.1.0.0 10.1.16.0 netmask 255.255.252.0 access-group OUT-TO-DMZ in interface outside access-group inside in interface inside access-group dmz in interface dmz route outside 0.0.0.0 0.0.0.0 41.223.156.108 1 timeout xlate 3:00:00 timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02 timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 timeout mgcp-pat 0:05:00 sip 0:30:00 sip_media 0:02:00 timeout uauth 0:05:00 absolute http server enable http 10.1.4.0 255.255.252.0 inside no snmp-server location no snmp-server contact snmp-server enable traps snmp authentication linkup linkdown coldstart crypto ipsec security-association lifetime seconds 28800 crypto ipsec security-association lifetime kilobytes 4608000 telnet timeout 5 ssh timeout 5 console timeout 0 management-access inside ! ! match default-inspection-traffic ! ! policy-map global_policy class inspection_default inspect dns maximum-length 512 inspect ftp inspect h323 h225 inspect h323 ras inspect netbios inspect rsh inspect rtsp inspect skinny inspect esmtp inspect sqlnet inspect sunrpc inspect tftp inspect sip inspect xdmcp ! service-policy global_policy global Cryptochecksum: : end ASA-FW# Please Help. Big Denzel

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• Hard drive after PCB swap strange stuff

  - by ramyy

  I’ve done a PCB swap to my HDD. The HDD model is: WD6400AAKS-00A7B2. The original PCB PN matches the new one (first three letter groups), though the cache mismatches (16MB original, 8MB new). The Hardware store that made the swap told me it was hard to do the swap, they have done firmware adaptation. I can see that this firmware version does not match the original, (01.03B01 original, 05.04E05 new). Still I can see that the serial number and model of the drive is correct, the hard drive appeared normal in the BIOS, all the partitions show and everything appears normal. I have encountered three things though, I have left the drive non operated for 2-3 weeks after the swap to avoid corrupting the data or anything else the new PCB might cause, until I buy a new drive and backup the data. I got a drive, and when I powered the old drive manually (I have a laptop, I use a normal desktop power supply and a USB/SATA connector), I heard the motor start and I could hear ticking as if the motor’s somehow struggling to start, and then the motor sound starts again then the ticking, and so on.. I tried powering again it happened again. The third time it started normally and I could see everything normally. I took the chance and copied all the data over to the new drive. When I was done, I powered off the drive (after more than 25 hours of continuous operation), tried to power it up again and it did so normally, and so are the times I powered it up later; but I got very suspicious now. What could be the problem here? And what happened new, it used to power normally after the swap directly? The second thing that happened is that I found size differences with some files; some include movies, songs, (.iso) files for games, and programs. I could find the size is the same, but size on disk is a little more on the new drive for these files. . I’ve tried some of those files (with size differences) they worked fine. They are not too much but still make you suspicious of the integrity of the data copied; one cannot try if all files are working for about (580 GB) worth of data. I tried copying these files on the same partition they exist of the old drive; they are the same in size as when copied to the new drive (allocation unit size not the issue). I took an image of a partition (sector by sector including empty ones) and when I explore it, these file sizes are equal to the original (old drive); I copy them anywhere else their size on disk, increases, i.e becomes equal to the ones I copy from the old drive itself anywhere. Why the size difference and can one trust the integrity of the data?? The third thing is that when I connect my new external USB HDD, the partitions of the old HDD unmount and then mount again. Connected are: (USB mouse + Old HDD) then external HDD. Why that happens?? Considering the following: I compared the SMART reports from after the swap directly and after the copying, no error readings or reallocated sectors where reported. Here they are: http://www.image-share.com/ijpg-1939-219.html I later ran both WD data life guard tests and they came out passed. I’m worried for this drive since I must be sure the data is fine and safe on the new one, and I will consider it backup for the new one, since you can’t trust anything anymore. I hope you can forgive me for the length of the post, but couldn’t ignore any of the details, this hard drive contains very important data to me and I have to deal with the situation with great care.

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• C#: Optional Parameters - Pros and Pitfalls

  - by James Michael Hare

  When Microsoft rolled out Visual Studio 2010 with C# 4, I was very excited to learn how I could apply all the new features and enhancements to help make me and my team more productive developers. Default parameters have been around forever in C++, and were intentionally omitted in Java in favor of using overloading to satisfy that need as it was though that having too many default parameters could introduce code safety issues.  To some extent I can understand that move, as I’ve been bitten by default parameter pitfalls before, but at the same time I feel like Java threw out the baby with the bathwater in that move and I’m glad to see C# now has them. This post briefly discusses the pros and pitfalls of using default parameters.  I’m avoiding saying cons, because I really don’t believe using default parameters is a negative thing, I just think there are things you must watch for and guard against to avoid abuses that can cause code safety issues. Pro: Default Parameters Can Simplify Code Let’s start out with positives.  Consider how much cleaner it is to reduce all the overloads in methods or constructors that simply exist to give the semblance of optional parameters.  For example, we could have a Message class defined which allows for all possible initializations of a Message: 1: public class Message 2: { 3: // can either cascade these like this or duplicate the defaults (which can introduce risk) 4: public Message() 5: : this(string.Empty) 6: { 7: } 8:  9: public Message(string text) 10: : this(text, null) 11: { 12: } 13:  14: public Message(string text, IDictionary<string, string> properties) 15: : this(text, properties, -1) 16: { 17: } 18:  19: public Message(string text, IDictionary<string, string> properties, long timeToLive) 20: { 21: // ... 22: } 23: }   Now consider the same code with default parameters: 1: public class Message 2: { 3: // can either cascade these like this or duplicate the defaults (which can introduce risk) 4: public Message(string text = "", IDictionary<string, string> properties = null, long timeToLive = -1) 5: { 6: // ... 7: } 8: }   Much more clean and concise and no repetitive coding!  In addition, in the past if you wanted to be able to cleanly supply timeToLive and accept the default on text and properties above, you would need to either create another overload, or pass in the defaults explicitly.  With named parameters, though, we can do this easily: 1: var msg = new Message(timeToLive: 100);   Pro: Named Parameters can Improve Readability I must say one of my favorite things with the default parameters addition in C# is the named parameters.  It lets code be a lot easier to understand visually with no comments.  Think how many times you’ve run across a TimeSpan declaration with 4 arguments and wondered if they were passing in days/hours/minutes/seconds or hours/minutes/seconds/milliseconds.  A novice running through your code may wonder what it is.  Named arguments can help resolve the visual ambiguity: 1: // is this days/hours/minutes/seconds (no) or hours/minutes/seconds/milliseconds (yes) 2: var ts = new TimeSpan(1, 2, 3, 4); 3:  4: // this however is visually very explicit 5: var ts = new TimeSpan(days: 1, hours: 2, minutes: 3, seconds: 4);   Or think of the times you’ve run across something passing a Boolean literal and wondered what it was: 1: // what is false here? 2: var sub = CreateSubscriber(hostname, port, false); 3:  4: // aha! Much more visibly clear 5: var sub = CreateSubscriber(hostname, port, isBuffered: false);   Pitfall: Don't Insert new Default Parameters In Between Existing Defaults Now let’s consider a two potential pitfalls.  The first is really an abuse.  It’s not really a fault of the default parameters themselves, but a fault in the use of them.  Let’s consider that Message constructor again with defaults.  Let’s say you want to add a messagePriority to the message and you think this is more important than a timeToLive value, so you decide to put messagePriority before it in the default, this gives you: 1: public class Message 2: { 3: public Message(string text = "", IDictionary<string, string> properties = null, int priority = 5, long timeToLive = -1) 4: { 5: // ... 6: } 7: }   Oh boy have we set ourselves up for failure!  Why?  Think of all the code out there that could already be using the library that already specified the timeToLive, such as this possible call: 1: var msg = new Message(“An error occurred”, myProperties, 1000);   Before this specified a message with a TTL of 1000, now it specifies a message with a priority of 1000 and a time to live of -1 (infinite).  All of this with NO compiler errors or warnings. So the rule to take away is if you are adding new default parameters to a method that’s currently in use, make sure you add them to the end of the list or create a brand new method or overload. Pitfall: Beware of Default Parameters in Inheritance and Interface Implementation Now, the second potential pitfalls has to do with inheritance and interface implementation.  I’ll illustrate with a puzzle: 1: public interface ITag 2: { 3: void WriteTag(string tagName = "ITag"); 4: } 5:  6: public class BaseTag : ITag 7: { 8: public virtual void WriteTag(string tagName = "BaseTag") { Console.WriteLine(tagName); } 9: } 10:  11: public class SubTag : BaseTag 12: { 13: public override void WriteTag(string tagName = "SubTag") { Console.WriteLine(tagName); } 14: } 15:  16: public static class Program 17: { 18: public static void Main() 19: { 20: SubTag subTag = new SubTag(); 21: BaseTag subByBaseTag = subTag; 22: ITag subByInterfaceTag = subTag; 23:  24: // what happens here? 25: subTag.WriteTag(); 26: subByBaseTag.WriteTag(); 27: subByInterfaceTag.WriteTag(); 28: } 29: }   What happens?  Well, even though the object in each case is SubTag whose tag is “SubTag”, you will get: 1: SubTag 2: BaseTag 3: ITag   Why?  Because default parameter are resolved at compile time, not runtime!  This means that the default does not belong to the object being called, but by the reference type it’s being called through.  Since the SubTag instance is being called through an ITag reference, it will use the default specified in ITag. So the moral of the story here is to be very careful how you specify defaults in interfaces or inheritance hierarchies.  I would suggest avoiding repeating them, and instead concentrating on the layer of classes or interfaces you must likely expect your caller to be calling from. For example, if you have a messaging factory that returns an IMessage which can be either an MsmqMessage or JmsMessage, it only makes since to put the defaults at the IMessage level since chances are your user will be using the interface only. So let’s sum up.  In general, I really love default and named parameters in C# 4.0.  I think they’re a great tool to help make your code easier to read and maintain when used correctly. On the plus side, default parameters: Reduce redundant overloading for the sake of providing optional calling structures. Improve readability by being able to name an ambiguous argument. But remember to make sure you: Do not insert new default parameters in the middle of an existing set of default parameters, this may cause unpredictable behavior that may not necessarily throw a syntax error – add to end of list or create new method. Be extremely careful how you use default parameters in inheritance hierarchies and interfaces – choose the most appropriate level to add the defaults based on expected usage. Technorati Tags: C#,.NET,Software,Default Parameters

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• Week in Geek: IPv6 Capable Smartphones Compromise User Privacy Edition

  - by Asian Angel

  This week we learned how to “clone a disk, resize static windows, and create system function shortcuts”, use 45 different services, sites, and apps to help read favorite sites, add MP3 support to Audacity (for saving in MP3 format), install a Wii game loader for easy backups and fast load times, create a Blue Screen of Death in any color, and more. Photo by legofenris. Weekly News Links Photo by The H Security. IPv6: Smartphones compromise users’ privacy Since version 4 of the iOS operating system, Apple’s iPhones, iPads and iPods have been capable of handling IPv6, and most Android devices have been capable since version 2.1. However, the operating systems transfer an ID that discloses information about their users. Dumb phones can be attacked too Much of the discussion of security threats to mobile phones revolves around smartphones, but researchers have found that less advanced “feature phones,” still used by the majority of people around the world, also are vulnerable to attack. SCADA exploit – the dragon awakes The recent publication of an exploit for KingView, a software package for visualising industrial process control systems, appears to be having an effect. Threatpost reports that both the Chinese vendor Wellintech and Chinese CERT (CN-CERT) have now reacted. Sophos: Spam to get more malicious Spam is becoming more malicious in nature as trickery tactics change in line with current user interests, according to a new report released Tuesday by Sophos. Global spam traffic rebounds as Rustock wakes Spam is on the rise after the Rustock botnet awoke from its Christmas slumber, according to Symantec. Cracking WPA keys in the cloud At the forthcoming Black Hat conference, blogger Thomas Roth plans to demonstrate how weak WPA PSKs can be cracked quickly and easily using Amazon’s Elastic Compute Cloud (EC2) service. Microsoft Security Advisory: Vulnerability in Internet Explorer could allow remote code execution Provides a link to more details about the vulnerability and shows a work-around/fix for the problem. Adobe plans to make it easier to delete Flash cookies in web browsers The new API, NPAPI:ClearSiteData, will allow Flash cookies – also known as Local Shared Objects (LSO) – to be deleted directly in the browser’s settings. Firefox beta getting new database standard The ninth beta version of Firefox is set to get support for a standard called IndexedDB that provides a database interface useful for offline data storage and other tasks needing information on a browser’s computer. MetroPCS accused of blocking certain Net content MetroPCS is violating the FCC’s recently approved Net neutrality rules by blocking certain Internet content, say several public interest groups. Server and Tools chief Muglia to leave Microsoft in summer 2011 Microsoft veteran and Server & Tools Business (STB) President Bob Muglia is leaving Microsoft, according to an email that CEO Steve Ballmer sent to employees on January 10. Report: DOJ nearing decision on Google-ITA The U.S. Department of Justice is gearing up for a possible formal antitrust investigation into whether or not Google should be allowed to purchase travel software company ITA Software, according to a report. South Korea says Google Street View broke law Police in South Korea reportedly say Google broke the country’s law when its Street View service captured personal data from unsecure Wi-Fi networks. The backlash over Google’s HTML5 video bet Choosing strategies based on what you believe to be long-term benefits is generally a good idea when running a business, but if you manage to alienate the world in the process, the long term may become irrelevant. Google answers critics on HTML5 Web video move Google responded to critics of its decision to drop support for a popular HTML5 video codec by declaring that a royalty-supported standard for Web video will hold the Web hostage. Random TinyHacker Links A Special GiveAway: a Great Book & Great Security Software The team from 7 Tutorials has a special giveaway running during the month of January. Signed copies of their latest book, full 1-year licenses of BitDefender Internet Security 2011 and free 3-month trials for everyone willing to participate. One Click Rooting For Android Phones Here’s a nice tool that helps you root your Android phone effortlessly. New Angry Birds Free version 1.0 Available in the App Store. Google Code University Learn programming at Google Code University. Capture and Share Your Favorite Part Of a YouTube Video SnipSnip.it lets you share only the part of the video that you like. Super User Questions More great questions and answers from this past week’s popular topics at Super User. What are the Windows A: and B: drives used for? Does OS X support linux-like features? What is the easiest way to make a backup of an entire hard disk? Will shifting from Wireless to Wired network result in better performance? Is it legal to install Windows 7 Home Premium Retail inside VMware virtual machine? How-To Geek Weekly Article Recap Enjoy reading through our hottest articles from this past week. The 50 Best Ways to Disable Built-in Windows Features You Don’t Want The Best of CES (Consumer Electronics Show) in 2011 How to Upgrade Windows 7 Easily (And Understand Whether You Should) The Worst of CES (Consumer Electronics Show) in 2011 The How-To Geek Guide to Audio Editing: Basic Noise Removal One Year Ago on How-To Geek More great articles from one year ago filled with helpful geeky goodness for you to enjoy. Share Text & Images the Easy Way with JustPaste.it Start Portable Firefox in Safe Mode Firefox 3.6 Release Candidate Available, Here’s How to Fix Your Incompatible Extensions Protect Your Computer from “Little Hands” with KidSafe Lock Prying Eyes Out of Your Minimized Windows Custom Crocheted Cylon-Cthulhu Hybrid What happens when you let your Cylon Centurion figure and your crocheted Cthulhu spend too many lonely nights together? A Cylon-Cthulhu hybrid, of course! You can get your own from the Cthulhu Chick store over on Etsy. Note: This is not an ad…Ruth is a friend of ours, and this Cylon-Cthulhu hybrid makes the perfect guard for the new MVP trophy in our office. The Geek Note Whether it is a geeky indoor project or just getting outside, we hope that you and your families have a terrific fun-filled weekend! Remember to keep sending those great tips in to us at [email protected]. Photo by qwrrty. Latest Features How-To Geek ETC How to Upgrade Windows 7 Easily (And Understand Whether You Should) The How-To Geek Guide to Audio Editing: Basic Noise Removal Install a Wii Game Loader for Easy Backups and Fast Load Times The Best of CES (Consumer Electronics Show) in 2011 The Worst of CES (Consumer Electronics Show) in 2011 HTG Projects: How to Create Your Own Custom Papercraft Toy Firefox 4.0 Beta 9 Available for Download – Get Your Copy Now The Frustrations of a Computer Literate Watching a Newbie Use a Computer [Humorous Video] Season0nPass Jailbreaks Current Gen Apple TVs IBM’s Jeopardy Playing Computer Watson Shows The Pros How It’s Done [Video] Tranquil Juice Drop Abstract Wallpaper Pulse Is a Sleek Newsreader for iOS and Android Devices

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