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• smartctl -t long isn't finishing

  - by xenoterracide

  I been running smartctl -t long on a drive for about 2 days now and it seems to be stalled at 10%. short and conveyance both passed. I have to send 1 of 2 drives purchased back I found badblocks with badblocks (none on this drive and I'ts made over a pass already). I'm just wondering if I should be concerned about this. smartctl 5.39.1 2010-01-28 r3054 [x86_64-unknown-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net === START OF INFORMATION SECTION === Device Model: WDC WD10EARS-00Y5B1 Serial Number: WD-WMAV51582123 Firmware Version: 80.00A80 User Capacity: 1,000,204,886,016 bytes Device is: Not in smartctl database [for details use: -P showall] ATA Version is: 8 ATA Standard is: Exact ATA specification draft version not indicated Local Time is: Mon May 10 22:19:52 2010 EDT SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED General SMART Values: Offline data collection status: (0x82) Offline data collection activity was completed without error. Auto Offline Data Collection: Enabled. Self-test execution status: ( 241) Self-test routine in progress... 10% of test remaining. Total time to complete Offline data collection: (20100) seconds. Offline data collection capabilities: (0x7b) SMART execute Offline immediate. Auto Offline data collection on/off support. Suspend Offline collection upon new command. Offline surface scan supported. Self-test supported. Conveyance Self-test supported. Selective Self-test supported. SMART capabilities: (0x0003) Saves SMART data before entering power-saving mode. Supports SMART auto save timer. Error logging capability: (0x01) Error logging supported. General Purpose Logging supported. Short self-test routine recommended polling time: ( 2) minutes. Extended self-test routine recommended polling time: ( 231) minutes. Conveyance self-test routine recommended polling time: ( 5) minutes. SCT capabilities: (0x3031) SCT Status supported. SCT Feature Control supported. SCT Data Table supported. SMART Attributes Data Structure revision number: 16 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x002f 200 200 051 Pre-fail Always - 2 3 Spin_Up_Time 0x0027 131 131 021 Pre-fail Always - 6408 4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 12 5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0 7 Seek_Error_Rate 0x002e 200 200 000 Old_age Always - 0 9 Power_On_Hours 0x0032 100 100 000 Old_age Always - 148 10 Spin_Retry_Count 0x0032 100 253 000 Old_age Always - 0 11 Calibration_Retry_Count 0x0032 100 253 000 Old_age Always - 0 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 10 192 Power-Off_Retract_Count 0x0032 200 200 000 Old_age Always - 7 193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 174 194 Temperature_Celsius 0x0022 106 102 000 Old_age Always - 41 196 Reallocated_Event_Count 0x0032 200 200 000 Old_age Always - 0 197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0030 200 200 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always - 0 200 Multi_Zone_Error_Rate 0x0008 200 200 000 Old_age Offline - 0 SMART Error Log Version: 1 No Errors Logged SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Conveyance offline Completed without error 00% 99 - # 2 Extended offline Interrupted (host reset) 10% 30 - # 3 Short offline Completed without error 00% 0 - SMART Selective self-test log data structure revision number 1 SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS 1 0 0 Not_testing 2 0 0 Not_testing 3 0 0 Not_testing 4 0 0 Not_testing 5 0 0 Not_testing Selective self-test flags (0x0): After scanning selected spans, do NOT read-scan remainder of disk. If Selective self-test is pending on power-up, resume after 0 minute delay.

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• How to debug solve 500 Internal error aws micro ec2 with suexec, Apache and php CGi

  - by Oudin

  I'm running WordPress multi-site on an amazon micro ec2 with suexec, Apache and php CGi On Ubuntu 12.04 However I've been experiencing a lot of Internal server 500 errors and I'm in the process of debugging it to find a solution. I've posted my error logs below example.com error.log: [Fri Oct 26 10:10:08 2012] [warn] [client 23.23.xxx.xx] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server [Fri Oct 26 10:10:08 2012] [error] [client 23.23.xxx.xx] Premature end of script headers: wp-cron.php [Fri Oct 26 10:50:04 2012] [warn] [client 190.213.xxx.xxx] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server, referer: https://www.example.com/wp-admin/ [Fri Oct 26 10:50:04 2012] [error] [client 190.213.xxx.xxx] Premature end of script headers: admin.php, referer: https://www.example.com/wp-admin/ [Fri Oct 26 10:58:14 2012] [warn] [client 190.213.xxx.xxx] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server, referer: https://www.example.com/wp-admin/network/index.php [Fri Oct 26 10:58:15 2012] [error] [client 190.213.xxx.xxx] Premature end of script headers: admin-ajax.php, referer: https://www.example.com/wp-admin/network/index.php [Fri Oct 26 10:58:56 2012] [warn] [client 190.213.xxx.xxx] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server, referer: https://www.example.com/wp-admin/network/index.php [Fri Oct 26 10:58:57 2012] [error] [client 190.213.xxx.xxx] Premature end of script headers: plugins.php, referer: https://www.example.com/wp-admin/network/index.php [Fri Oct 26 10:59:18 2012] [warn] [client 190.213.xxx.xxx] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server, referer: https://www.example.com/wp-admin/network/index.php [Fri Oct 26 10:59:18 2012] [error] [client 190.213.xxx.xxx] Premature end of script headers: admin-ajax.php, referer: https://www.example.com/wp-admin/network/index.php [Fri Oct 26 11:01:49 2012] [warn] [client 190.213.xxx.xxx] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server, referer: https://www.example.com/wp-admin/ [Fri Oct 26 11:01:49 2012] [warn] [client 190.213.xxx.xxx] (104)Connection reset by peer: mod_fcgid: ap_pass_brigade failed in handle_request_ipc function, referer: https://www.example.com/wp-admin/ Apache Log: php (pre-forking): Cannot allocate memory php (pre-forking): Cannot allocate memory Recipient names must be specified Recipient names must be specified php (pre-forking): Cannot allocate memory php (pre-forking): Cannot allocate memory php (pre-forking): Cannot allocate memory [Fri Oct 26 10:49:33 2012] [warn] mod_fcgid: cleanup zombie process 2852 [Fri Oct 26 10:49:33 2012] [warn] mod_fcgid: cleanup zombie process 2851 [Fri Oct 26 10:49:33 2012] [warn] mod_fcgid: cleanup zombie process 2853 [Fri Oct 26 10:58:22 2012] [warn] mod_fcgid: process 2892 graceful kill fail, sending SIGKILL php (pre-forking): Cannot allocate memory [Fri Oct 26 10:59:21 2012] [warn] mod_fcgid: process 2894 graceful kill fail, sending SIGKILL [Fri Oct 26 10:59:25 2012] [warn] mod_fcgid: process 2866 graceful kill fail, sending SIGKILL suexec.log: [2012-10-25 16:05:36]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 18:09:38]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 18:09:51]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 18:14:03]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 18:14:06]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 18:14:35]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 20:20:27]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 20:20:29]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 20:20:31]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 21:42:12]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-25 22:56:50]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-26 02:34:43]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-26 04:25:07]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-26 06:35:19]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-26 06:40:05]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-26 07:22:45]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-26 10:10:05]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-26 10:49:24]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi [2012-10-26 10:49:24]: uid: (1002/username) gid: (1002/username) cmd: php-fcgi based on the logs can any determine what might be the cause of this? Thinking that it might be the micro instance I'm thinking of upgrading to a small. Any help would be greatly appreciated.

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• Exchange 2003 mail non-delivery (NDR), spam activity? events 7002 & 7004

  - by HighTechGeek

  Windows Server 2003 Small Business Server SP2 Exchange Version 6.5 (Build 7638.2: Service Pack 2) This network has been neglected and has been having email problems for years and was on many blacklists. I was called in after the server eventually crashed... I got the server back up and running, but email problems persist. Outgoing mail delivery is sporadic. Sometimes the mail goes through, sometimes a delayed delivery report is generated after a day or more, and sometimes it seems to go through, but the recipient never receives it. Not sure if spammers are successfully using the server as a relay (see event entries below after turning on maximum SMTP logging)... User PCs infected with viruses and server was blacklisted on many sites (I used mxtoolbox.com) I have cleaned all the PCs and changed all passwords (including administrator) I have requested removal from all of the blacklists - most have removed the listing, some take more time. I have setup rDNS pointer records with the ISP (Comcast) - that was one reason for some of the blacklistings. I have tested that it's not an open relay using telnet as described here: www.amset.info/exchange/smtp-openrelay.asp I followed the advise of a Spamhaus & Microsoft article to enable maximum SMTP logging. http://www.spamhaus.org/faq/answers.lasso?section=isp%20spam%20issues#320 which directed me to Microsoft KB article 895853, specifically, the part 2/3 down titled: "If mail relay occurs from an account on an Exchange computer that is not configured as an open relay" . The Application Event Log is filling with this type of activity (Event ID 7002, 7002 & 3018 errors): Event Type: Error Event Source: MSExchangeTransport Event Category: SMTP Protocol Event ID: 7004 Date: 1/18/2011 Time: 7:33:29 AM User: N/A Computer: SERVER Description: This is an SMTP protocol error log for virtual server ID 1, connection #621. The remote host "212.52.84.180", responded to the SMTP command "rcpt" with "550 #5.1.0 Address rejected [email protected] ". The full command sent was "RCPT TO: ". This will probably cause the connection to fail. and this: Event Type: Warning Event Source: MSExchangeTransport Event Category: SMTP Protocol Event ID: 7002 Date: 1/18/2011 Time: 7:33:29 AM User: N/A Computer: SERVER Description: This is an SMTP protocol warning log for virtual server ID 1, connection #620. The remote host "212.52.84.170", responded to the SMTP command "rcpt" with "452 Too many recipients received this hour ". The full command sent was "RCPT TO: ". This may cause the connection to fail. or a variant of: Event Type: Warning Event Source: MSExchangeTransport Event Category: SMTP Protocol Event ID: 7002 Date: 1/18/2011 Time: 8:39:21 AM User: N/A Computer: SERVER Description: This is an SMTP protocol warning log for virtual server ID 1, connection #661. The remote host "82.57.200.133", responded to the SMTP command "rcpt" with "421 Service not available - too busy ". The full command sent was "RCPT TO: ". This may cause the connection to fail. also Event Type: Error Event Source: MSExchangeTransport Event Category: NDR Event ID: 3018 Date: 1/18/2011 Time: 9:49:37 AM User: N/A Computer: SERVER Description: A non-delivery report with a status code of 5.4.0 was generated for recipient rfc822;[email protected] (Message-ID ). Causes: This message indicates a DNS problem or an IP address configuration problem Solution: Check the DNS using nslookup or dnsq. Verify the IP address is in IPv4 literal format. Data: 0000: ef 02 04 c0 ï..À Any guidance and/or suggestions and/or tests to perform would be greatly appreciated.

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• why is $0 set to -bash?

  - by James Shimer

  First login process name seems to be set to "-bash", but if I subshell then it becomes "bash". for example: root@nowere:~# echo $0 -bash root@nowere:~# bash root@nowere:~# echo $0 bash -bash is causing some scripts to fail, such as . /usr/share/debconf/confmodule exec /usr/share/debconf/frontend -bash Can't exec "-bash": No such file or directory at /usr/share/perl/5.14/IPC/Open3.pm line 186. open2: exec of -bash failed at /usr/share/perl5/Debconf/ConfModule.pm line 59 Anyone know the reason $0 is set to -bash?

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• Virtualbox on Ubuntu 12.04 and 3.5 kernel

  - by kas

  I have installed the 3.5 kernel under Ubuntu 12.04. When I install virtualbox I recieve the following error. Setting up virtualbox (4.1.12-dfsg-2ubuntu0.2) ... * Stopping VirtualBox kernel modules [ OK ] * Starting VirtualBox kernel modules * No suitable module for running kernel found [fail] invoke-rc.d: initscript virtualbox, action "restart" failed. Processing triggers for python-central ... Setting up virtualbox-dkms (4.1.12-dfsg-2ubuntu0.2) ... Loading new virtualbox-4.1.12 DKMS files... First Installation: checking all kernels... Building only for 3.5.0-18-generic Building initial module for 3.5.0-18-generic Error! Bad return status for module build on kernel: 3.5.0-18-generic (x86_64) Consult /var/lib/dkms/virtualbox/4.1.12/build/make.log for more information. * Stopping VirtualBox kernel modules [ OK ] * Starting VirtualBox kernel modules * No suitable module for running kernel found [fail] invoke-rc.d: initscript virtualbox, action "restart" failed. Setting up virtualbox-qt (4.1.12-dfsg-2ubuntu0.2) ... Does anyone know how I might be able to resolve this? Edit -- Here is the make.log DKMS make.log for virtualbox-4.1.12 for kernel 3.5.0-18-generic (x86_64) Mon Nov 19 12:12:23 EST 2012 make: Entering directory `/usr/src/linux-headers-3.5.0-18-generic' LD /var/lib/dkms/virtualbox/4.1.12/build/built-in.o LD /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/built-in.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/linux/SUPDrv-linux.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/SUPDrv.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/SUPDrvSem.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/alloc-r0drv.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/initterm-r0drv.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/memobj-r0drv.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/mpnotification-r0drv.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/powernotification-r0drv.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/linux/assert-r0drv-linux.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/linux/alloc-r0drv-linux.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/linux/initterm-r0drv-linux.o CC [M] /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/linux/memobj-r0drv-linux.o /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/linux/memobj-r0drv-linux.c: In function ‘rtR0MemObjLinuxDoMmap’: /var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/linux/memobj-r0drv-linux.c:1150:9: error: implicit declaration of function ‘do_mmap’ [-Werror=implicit-function-declaration] cc1: some warnings being treated as errors make[2]: *** [/var/lib/dkms/virtualbox/4.1.12/build/vboxdrv/r0drv/linux/memobj-r0drv-linux.o] Error 1 make[1]: *** [/var/lib/dkms/virtualbox/4.1.12/build/vboxdrv] Error 2 make: *** [_module_/var/lib/dkms/virtualbox/4.1.12/build] Error 2 make: Leaving directory `/usr/src/linux-headers-3.5.0-18-generic'

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• SQLAuthority News – Pluralsight Course Review – Practices for Software Startups – Part 1 of 2

  - by pinaldave

  This is first part of the two part series of Practices for Software Startup Pluralsight Course. The course is written by Stephen Forte (Blog | Twitter). Stephen Forte is the Chief Strategy Officer of the venture backed company, Telerik, a leading vendor of developer and team productivity tools. Stephen is also a Certified Scrum Master, Certified Scrum Professional, PMP, and also speaks regularly at industry conferences around the world. He has written several books on application and database development.  Stephen is also a board member of the Scrum Alliance. Startups – Everybodies Dream Start-up companies are an important topic right now – everyone wants to start their own business.  It is also important to remember that all companies were a start up at one point – from your corner store to the giants like Microsoft and Apple.  Research proves that not every start-up succeeds, in fact, most will fail before their first year.  There are many reasons for this, and this could be due to the fact that there are many stages to a start-up company, and stumbling at any of these stages can lead to failure.  It is important to understand what makes a start-up company succeed at all its hurdles to become successful.  It is even important to define success.  For most start-ups this would mean becoming their own independently functioning company or to be bought out for a hefty profit by a larger company.  The idea of making a hefty profit by living your dream is extremely important, and you can even think of start-ups as the new craze.  That’s why studying them is so important – they are very popular, but things have changed a lot since their inception. Starting the Startups Beginning a start-up company used to be difficult, but now facilities and information is widely available, and it is much easier.  But that means it is much easier to fail, also.  Previously to start your own company, everything was planned and organized, resources were ensured and backed up before beginning; even the idea of starting your own business was a big thing.  Now anybody can do it, and the steps are simple and outlines everywhere – you can get online software and easily outsource , cloud source, or crowdsource a lot of your material.  But without the type of planning previously required, things can often go badly. New Products – New Ideas – New World There are so many fantastic new products, but they don’t reach success all the time.  I find start-up companies very interesting, and whenever I meet someone who is interested in the subject or already starting their own company, I always ask what they are doing, their plans, goals, market, etc.  I am sorry to say that in most cases, they cannot answer my questions.  It is true that many fantastic ideas fail because of bad decisions.  These bad decisions were not made intentionally, but people were simply unaware of what they should be doing.  This will always lead to failure.  But I am happy to say that all these issues can be gone because Pluralsight is now offering a course all about start-ups by Stephen Forte.  Stephen is a start up leader.  He has successfully started many companies and most are still going strong, or have gone on to even bigger and better things. Beginning Course on Startup I have always thought start-ups are a fascinating subject, and decided to take his course, but it is three hours long.  This would be hard to fit into my busy work day all at once, so I decided to do half of his course before my daughter wakes up, and the other half after she goes to sleep.  The course is divided into six modules, so this would be easy to do.  I began the first chapter early in the morning, at 5 am.  Stephen jumped right into the middle of the subject in the very first module – designing your business plan.  The first question you will have to answer to yourself, to others, and to investors is: What is your product and when will we be able to see it?  So a very important concept is a “minimal viable product.”  This means setting goals for yourself and your product.  We all have large dreams, but your minimal viable product doesn’t have to be your final vision at the very first.  For example: Apple is a giant company, but it is still evolving.  Steve Jobs didn’t envision the iPhone 6 at the very beginning.  He had to start at the first iPhone and do his market research, and the idea evolved into the technology you see now.  So for yourself, you should decide a beginning and stop point.  Do your market research.  Determine who you want to reach, what audience you want for your product.  You can have a great idea that simply will not work in the market, do need, bottlenecks, lack of resources, or competition.  There is a lot of research that needs to be done before you even write a business plan, and Stephen covers it in the very first chapter. The Team – Unique Key to Success After jumping right into the subject in the very first module, I wondered what Stephen could have in store for me for the rest of the course.  Chapter number two is building a team.  Having a team is important regardless of what your startup is.  You can be a true visionary with endless ideas and energy, but one person can still not do everything.  It is important to decide from the very beginning if you will have cofounders, team leaders, and how many employees you’ll need.  Even more important, you’ll need to decide what kind of team you want – what personalities, skills, and type of energy you want each of your employees to bring.  Do you want to have an A+ team with a B- idea, or do you have a B- idea that needs an A+ team to sell it?  Stephen asks all the hard questions!  I was especially impressed by his insight on developing.  You have to decide if you need developers, how many, and what their skills should be. I found this insight extremely useful for everyday usage, not just for start-up companies.  I would apply this kind of information in management at any position.  An amazing team will build an amazing product – and that doesn’t matter if you’re a start-up company or a small team working for a much larger business. Customer Development – The Ultimate Obective Chapter three was about customer development. According to Stephen, there are four different steps to develop a customer base.  The first question to ask yourself is if you are envisioning a large customer base buying a few products each, or a small, dedicated base that buys a lot of your product – quantity vs. Quality.  He also discusses how to earn, retain, and get more customers.  He also says that each customer should be placed in a different role – some will be like investors, who regularly spend with you and invest their money in your business.  It is then your job to take that investment and turn it into a better product in the future.  You need to deal with their money properly – think of it is as theirs as investors, not yours as profit.  At the end of this module I felt that only Stephen could provide this kind of insight, and then he listed all the resources he took his information from.  I have never seen a group of people so passionate about their customers. It was indeed a long day for me. In tomorrow’s part 2 we will discuss rest of the three module and also will see a quick video of the Practices for Software Startup Pluralsight Course. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Best Practices, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Transactions in LINQ to SQL applications

  - by nikolaosk

  In this post I would like to talk about LINQ to SQL and transactions.When I have a LINQ to SQL class I always get asked this question, "How does LINQ treat Transactions?". When we use the DeleteOnSubmit() method or the InsertOnSubmit() method, all of those commands at some point are translated into T-SQL commands and then are executed against the database. All of those commands live in transactions and they follow the basic rules of transaction processing. They do succeed together or fail together...(read more)

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• C#/.NET Little Pitfalls: The Dangers of Casting Boxed Values

  - by James Michael Hare

  Starting a new series to parallel the Little Wonders series.  In this series, I will examine some of the small pitfalls that can occasionally trip up developers. Introduction: Of Casts and Conversions What happens when we try to assign from an int and a double and vice-versa? 1: double pi = 3.14; 2: int theAnswer = 42; 3:  4: // implicit widening conversion, compiles! 5: double doubleAnswer = theAnswer; 6:  7: // implicit narrowing conversion, compiler error! 8: int intPi = pi; As you can see from the comments above, a conversion from a value type where there is no potential data loss is can be done with an implicit conversion.  However, when converting from one value type to another may result in a loss of data, you must make the conversion explicit so the compiler knows you accept this risk.  That is why the conversion from double to int will not compile with an implicit conversion, we can make the conversion explicit by adding a cast: 1: // explicit narrowing conversion using a cast, compiler 2: // succeeds, but results may have data loss: 3: int intPi = (int)pi; So for value types, the conversions (implicit and explicit) both convert the original value to a new value of the given type.  With widening and narrowing references, however, this is not the case.  Converting reference types is a bit different from converting value types.  First of all when you perform a widening or narrowing you don’t really convert the instance of the object, you just convert the reference itself to the wider or narrower reference type, but both the original and new reference type both refer back to the same object. Secondly, widening and narrowing for reference types refers the going down and up the class hierarchy instead of referring to precision as in value types.  That is, a narrowing conversion for a reference type means you are going down the class hierarchy (for example from Shape to Square) whereas a widening conversion means you are going up the class hierarchy (from Square to Shape).  1: var square = new Square(); 2:  3: // implicitly convers because all squares are shapes 4: // (that is, all subclasses can be referenced by a superclass reference) 5: Shape myShape = square; 6:  7: // implicit conversion not possible, not all shapes are squares! 8: // (that is, not all superclasses can be referenced by a subclass reference) 9: Square mySquare = (Square) myShape; So we had to cast the Shape back to Square because at that point the compiler has no way of knowing until runtime whether the Shape in question is truly a Square.  But, because the compiler knows that it’s possible for a Shape to be a Square, it will compile.  However, if the object referenced by myShape is not truly a Square at runtime, you will get an invalid cast exception. Of course, there are other forms of conversions as well such as user-specified conversions and helper class conversions which are beyond the scope of this post.  The main thing we want to focus on is this seemingly innocuous casting method of widening and narrowing conversions that we come to depend on every day and, in some cases, can bite us if we don’t fully understand what is going on!  The Pitfall: Conversions on Boxed Value Types Can Fail What if you saw the following code and – knowing nothing else – you were asked if it was legal or not, what would you think: 1: // assuming x is defined above this and this 2: // assignment is syntactically legal. 3: x = 3.14; 4:  5: // convert 3.14 to int. 6: int truncated = (int)x; You may think that since x is obviously a double (can’t be a float) because 3.14 is a double literal, but this is inaccurate.  Our x could also be dynamic and this would work as well, or there could be user-defined conversions in play.  But there is another, even simpler option that can often bite us: what if x is object? 1: object x; 2:  3: x = 3.14; 4:  5: int truncated = (int) x; On the surface, this seems fine.  We have a double and we place it into an object which can be done implicitly through boxing (no cast) because all types inherit from object.  Then we cast it to int.  This theoretically should be possible because we know we can explicitly convert a double to an int through a conversion process which involves truncation. But here’s the pitfall: when casting an object to another type, we are casting a reference type, not a value type!  This means that it will attempt to see at runtime if the value boxed and referred to by x is of type int or derived from type int.  Since it obviously isn’t (it’s a double after all) we get an invalid cast exception! Now, you may say this looks awfully contrived, but in truth we can run into this a lot if we’re not careful.  Consider using an IDataReader to read from a database, and then attempting to select a result row of a particular column type: 1: using (var connection = new SqlConnection("some connection string")) 2: using (var command = new SqlCommand("select * from employee", connection)) 3: using (var reader = command.ExecuteReader()) 4: { 5: while (reader.Read()) 6: { 7: // if the salary is not an int32 in the SQL database, this is an error! 8: // doesn't matter if short, long, double, float, reader [] returns object! 9: total += (int) reader["annual_salary"]; 10: } 11: } Notice that since the reader indexer returns object, if we attempt to convert using a cast to a type, we have to make darn sure we use the true, actual type or this will fail!  If the SQL database column is a double, float, short, etc this will fail at runtime with an invalid cast exception because it attempts to convert the object reference! So, how do you get around this?  There are two ways, you could first cast the object to its actual type (double), and then do a narrowing cast to on the value to int.  Or you could use a helper class like Convert which analyzes the actual run-time type and will perform a conversion as long as the type implements IConvertible. 1: object x; 2:  3: x = 3.14; 4:  5: // if you want to cast, must cast out of object to double, then 6: // cast convert. 7: int truncated = (int)(double) x; 8:  9: // or you can call a helper class like Convert which examines runtime 10: // type of the value being converted 11: int anotherTruncated = Convert.ToInt32(x); Summary You should always be careful when performing a conversion cast from values boxed in object that you are actually casting to the true type (or a sub-type). Since casting from object is a widening of the reference, be careful that you either know the exact, explicit type you expect to be held in the object, or instead avoid the cast and use a helper class to perform a safe conversion to the type you desire. Technorati Tags: C#,.NET,Pitfalls,Little Pitfalls,BlackRabbitCoder

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• EPM 11.1.2 - Configure a data source to support Essbase failover in active-passive clustering mode

  - by Ahmed A

  To configure a data source to support Essbase fail-over in active-passive clustering mode, replace the Essbase Server name value with the APS URL followed by the Essbase cluster name; for example, if the APS URL is http://<hostname>:13090/aps and the Essbase cluster name is EssbaseCluster-1, then the value in the Essbase Server name field would be:http://<hostname>:13090/aps/Essbase?clusterName=EssbaseCluster-1Note: Entering the Essbase cluster name without the APS URL in the Essbase Server name field is not supported in this release.

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• Survey Probes the Project Management Concerns of Financial Services Executives

  - by Melissa Centurio Lopes

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:0in; mso-para-margin-bottom:.0001pt; 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;} Do you wonder what are the top reasons why large projects in the financial industry fail to meet budgets, schedules, and other key performance criteria? Being able to answer this question can provide important insight and value of good project management practices for your organization. According to 400 senior executives who participated in a new survey conducted by the Economist Intelligence Unit and sponsored by Oracle, unrealistic project goals is the main reason for roadblocks to success Other common stumbling blocks are poor alignment between project and organizational goals, inadequate human resources, lack of strong leadership, and unwillingness among team members to point out problems. This survey sample also had a lot to say about the impact of regulatory compliance on the overall portfolio management process. Thirty-nine percent acknowledged that regulations enabled efficient functioning of their businesses. But a similar number said that regulations often require more financial resources than were originally allocated to bring projects in on time. Regulations were seen by 35 percent of the executives as roadblocks to their ability to invest in the organization’s growth and success. These revelations among others are discussed in depth in a new on-demand Webcast titled “Too Good to Fail: Developing Project Management Expertise in Financial Services” now available from Oracle. The Webcast features Brian Gardner, editor of the Economist Intelligence Unit, who presents these findings from this survey along with Guy Barlow, director of industry strategy for Oracle Primavera. Together, they analyze what the numbers mean for project and program managers and the financial services industry. Register today to watch the on-demand Webcast and get a full rundown and analysis of the survey results. Take the Economist Intelligence Unit benchmarking survey and see how your views compare with those of other financial services industry executives in ensuring project success.  Read more in the October Edition of the quarterly Information InDepth EPPM Newsletter

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• Apparmor not starting with kernel LSM error

  - by Roberto Aloi

  Starting apparmor on a Ubuntu Lucid Lynx gives the following: user@host:~$ sudo /etc/init.d/apparmor start * Starting AppArmor profiles * AppArmor not available as kernel LSM. ...fail! Googling a bit, I found the following bug report - marked as fixed -: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/375422 Which seems to be my exact case. My kernel is 2.6.32-21-generic. Any idea on how to solve the issue?

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• When You are Asked to Help with Internet Issues [Comic]

  - by Asian Angel

  We all know what that ‘first glance’ sinking feeling is like… Internet issues (Kelly Angel – Anything About Nothing! Blog) [via Fail Desk] Why Does 64-Bit Windows Need a Separate “Program Files (x86)” Folder? Why Your Android Phone Isn’t Getting Operating System Updates and What You Can Do About It How To Delete, Move, or Rename Locked Files in Windows

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• The Basics of Desktop Data Recovery

  Desktop data recovery is an important part of computer repairs, as it is pretty common for a hard drive or server RAID to fail and lose major amounts of data. With desktops especially, it is sometime... [Author: Richard Cuthbertson - Computers and Internet - April 07, 2010]

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• No Rush, Defragging that Drive can Wait [Humorous Image]

  - by Asian Angel

  That drive is only fragmented a little bit…nothing to worry about there. View a Larger Version of the Image You should defragment this volume. Ya think?! [via Fail Desk] What’s the Difference Between Sleep and Hibernate in Windows? Screenshot Tour: XBMC 11 Eden Rocks Improved iOS Support, AirPlay, and Even a Custom XBMC OS How To Be Your Own Personal Clone Army (With a Little Photoshop)

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• Segfault when iterating over a map<string, string> and drawing its contents using SDL_TTF

  - by Michael Stahre

  I'm not entirely sure this question belongs on gamedev.stackexchange, but I'm technically working on a game and working with SDL, so it might not be entirely offtopic. I've written a class called DebugText. The point of the class is to have a nice way of printing values of variables to the game screen. The idea is to call SetDebugText() with the variables in question every time they change or, as is currently the case, every time the game's Update() is called. The issue is that when iterating over the map that contains my variables and their latest updated values, I get segfaults. See the comments in DrawDebugText() below, it specifies where the error happens. I've tried splitting the calls to it-first and it-second into separate lines and found that the problem doesn't always happen when calling it-first. It alters between it-first and it-second. I can't find a pattern. It doesn't fail on every call to DrawDebugText() either. It might fail on the third time DrawDebugText() is called, or it might fail on the fourth. Class header: #ifndef CLIENT_DEBUGTEXT_H #define CLIENT_DEBUGTEXT_H #include <Map> #include <Math.h> #include <sstream> #include <SDL.h> #include <SDL_ttf.h> #include "vector2.h" using std::string; using std::stringstream; using std::map; using std::pair; using game::Vector2; namespace game { class DebugText { private: TTF_Font* debug_text_font; map<string, string>* debug_text_list; public: void SetDebugText(string var, bool value); void SetDebugText(string var, float value); void SetDebugText(string var, int value); void SetDebugText(string var, Vector2 value); void SetDebugText(string var, string value); int DrawDebugText(SDL_Surface*, SDL_Rect*); void InitDebugText(); void Clear(); }; } #endif Class source file: #include "debugtext.h" namespace game { // Copypasta function for handling the toString conversion template <class T> inline string to_string (const T& t) { stringstream ss (stringstream::in | stringstream::out); ss << t; return ss.str(); } // Initializes SDL_TTF and sets its font void DebugText::InitDebugText() { if(TTF_WasInit()) TTF_Quit(); TTF_Init(); debug_text_font = TTF_OpenFont("LiberationSans-Regular.ttf", 16); TTF_SetFontStyle(debug_text_font, TTF_STYLE_NORMAL); } // Iterates over the current debug_text_list and draws every element on the screen. // After drawing with SDL you need to get a rect specifying the area on the screen that was changed and tell SDL that this part of the screen needs to be updated. this is done in the game's Draw() function // This function sets rects_to_update to the new list of rects provided by all of the surfaces and returns the number of rects in the list. These two parameters are used in Draw() when calling on SDL_UpdateRects(), which takes an SDL_Rect* and a list length int DebugText::DrawDebugText(SDL_Surface* screen, SDL_Rect* rects_to_update) { if(debug_text_list == NULL) return 0; if(!TTF_WasInit()) InitDebugText(); rects_to_update = NULL; // Specifying the font color SDL_Color font_color = {0xff, 0x00, 0x00, 0x00}; // r, g, b, unused int row_count = 0; string line; // The iterator variable map<string, string>::iterator it; // Gets the iterator and iterates over it for(it = debug_text_list->begin(); it != debug_text_list->end(); it++) { // Takes the first value (the name of the variable) and the second value (the value of the parameter in string form) //---------THIS LINE GIVES ME SEGFAULTS----- line = it->first + ": " + it->second; //------------------------------------------ // Creates a surface with the text on it that in turn can be rendered to the screen itself later SDL_Surface* debug_surface = TTF_RenderText_Solid(debug_text_font, line.c_str(), font_color); if(debug_surface == NULL) { // A standard check for errors fprintf(stderr, "Error: %s", TTF_GetError()); return NULL; } else { // If SDL_TTF did its job right, then we now set a destination rect row_count++; SDL_Rect dstrect = {5, 5, 0, 0}; // x, y, w, h dstrect.x = 20; dstrect.y = 20*row_count; // Draws the surface with the text on it to the screen int res = SDL_BlitSurface(debug_surface,NULL,screen,&dstrect); if(res != 0) { //Just an error check fprintf(stderr, "Error: %s", SDL_GetError()); return NULL; } // Creates a new rect to specify the area that needs to be updated with SDL_Rect* new_rect_to_update = (SDL_Rect*) malloc(sizeof(SDL_Rect)); new_rect_to_update->h = debug_surface->h; new_rect_to_update->w = debug_surface->w; new_rect_to_update->x = dstrect.x; new_rect_to_update->y = dstrect.y; // Just freeing the surface since it isn't necessary anymore SDL_FreeSurface(debug_surface); // Creates a new list of rects with room for the new rect SDL_Rect* newtemp = (SDL_Rect*) malloc(row_count*sizeof(SDL_Rect)); // Copies the data from the old list of rects to the new one memcpy(newtemp, rects_to_update, (row_count-1)*sizeof(SDL_Rect)); // Adds the new rect to the new list newtemp[row_count-1] = *new_rect_to_update; // Frees the memory used by the old list free(rects_to_update); // And finally redirects the pointer to the old list to the new list rects_to_update = newtemp; newtemp = NULL; } } // When the entire map has been iterated over, return the number of lines that were drawn, ie. the number of rects in the returned rect list return row_count; } // The SetDebugText used by all the SetDebugText overloads // Takes two strings, inserts them into the map as a pair void DebugText::SetDebugText(string var, string value) { if (debug_text_list == NULL) { debug_text_list = new map<string, string>(); } debug_text_list->erase(var); debug_text_list->insert(pair<string, string>(var, value)); } // Writes the bool to a string and calls SetDebugText(string, string) void DebugText::SetDebugText(string var, bool value) { string result; if (value) result = "True"; else result = "False"; SetDebugText(var, result); } // Does the same thing, but uses to_string() to convert the float void DebugText::SetDebugText(string var, float value) { SetDebugText(var, to_string(value)); } // Same as above, but int void DebugText::SetDebugText(string var, int value) { SetDebugText(var, to_string(value)); } // Vector2 is a struct of my own making. It contains the two float vars x and y void DebugText::SetDebugText(string var, Vector2 value) { SetDebugText(var + ".x", to_string(value.x)); SetDebugText(var + ".y", to_string(value.y)); } // Empties the list. I don't actually use this in my code. Shame on me for writing something I don't use. void DebugText::Clear() { if(debug_text_list != NULL) debug_text_list->clear(); } }

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• SQL University: Database testing and refactoring tools and examples

  - by Mladen Prajdic

  This is a post for a great idea called SQL University started by Jorge Segarra also famously known as SqlChicken on Twitter. It’s a collection of blog posts on different database related topics contributed by several smart people all over the world. So this week is mine and we’ll be talking about database testing and refactoring. In 3 posts we’ll cover: SQLU part 1 - What and why of database testing SQLU part 2 - What and why of database refactoring SQLU part 3 - Database testing and refactoring tools and examples This is the third and last part of the series and in it we’ll take a look at tools we can test and refactor with plus some an example of the both. Tools of the trade First a few thoughts about how to go about testing a database. I'm firmily against any testing tools that go into the database itself or need an extra database. Unit tests for the database and applications using the database should all be in one place using the same technology. By using database specific frameworks we fragment our tests into many places and increase test system complexity. Let’s take a look at some testing tools. 1. NUnit, xUnit, MbUnit All three are .Net testing frameworks meant to unit test .Net application. But we can test databases with them just fine. I use NUnit because I’ve always used it for work and personal projects. One day this might change. So the thing to remember is to be flexible if something better comes along. All three are quite similar and you should be able to switch between them without much problem. 2. TSQLUnit As much as this framework is helpful for the non-C# savvy folks I don’t like it for the reason I stated above. It lives in the database and thus fragments the testing infrastructure. Also it appears that it’s not being actively developed anymore. 3. DbFit I haven’t had the pleasure of trying this tool just yet but it’s on my to-do list. From what I’ve read and heard Gojko Adzic (@gojkoadzic on Twitter) has done a remarkable job with it. 4. Redgate SQL Refactor and Apex SQL Refactor Neither of these refactoring tools are free, however if you have hardcore refactoring planned they are worth while looking into. I’ve only used the Red Gate’s Refactor and was quite impressed with it. 5. Reverting the database state I’ve talked before about ways to revert a database to pre-test state after unit testing. This still holds and I haven’t changed my mind. Also make sure to read the comments as they are quite informative. I especially like the idea of setting up and tearing down the schema for each test group with NHibernate. Testing and refactoring example We’ll take a look at the simple schema and data test for a view and refactoring the SELECT * in that view. We’ll use a single table PhoneNumbers with ID and Phone columns. Then we’ll refactor the Phone column into 3 columns Prefix, Number and Suffix. Lastly we’ll remove the original Phone column. Then we’ll check how the view behaves with tests in NUnit. The comments in code explain the problem so be sure to read them. I’m assuming you know NUnit and C#. T-SQL Code C# test code USE tempdbGOCREATE TABLE PhoneNumbers( ID INT IDENTITY(1,1), Phone VARCHAR(20))GOINSERT INTO PhoneNumbers(Phone)SELECT '111 222333 444' UNION ALLSELECT '555 666777 888'GO-- notice we don't have WITH SCHEMABINDINGCREATE VIEW vPhoneNumbersAS SELECT * FROM PhoneNumbersGO-- Let's take a look at what the view returns -- If we add a new columns and rows both tests will failSELECT *FROM vPhoneNumbers GO -- DoesViewReturnCorrectColumns test will SUCCEED -- DoesViewReturnCorrectData test will SUCCEED -- refactor to split Phone column into 3 partsALTER TABLE PhoneNumbers ADD Prefix VARCHAR(3)ALTER TABLE PhoneNumbers ADD Number VARCHAR(6)ALTER TABLE PhoneNumbers ADD Suffix VARCHAR(3)GO-- update the new columnsUPDATE PhoneNumbers SET Prefix = LEFT(Phone, 3), Number = SUBSTRING(Phone, 5, 6), Suffix = RIGHT(Phone, 3)GO-- remove the old columnALTER TABLE PhoneNumbers DROP COLUMN PhoneGO-- This returns unexpected results!-- it returns 2 columns ID and Phone even though -- we don't have a Phone column anymore.-- Notice that the data is from the Prefix column-- This is a danger of SELECT *SELECT *FROM vPhoneNumbers -- DoesViewReturnCorrectColumns test will SUCCEED -- DoesViewReturnCorrectData test will FAIL -- for a fix we have to call sp_refreshview -- to refresh the view definitionEXEC sp_refreshview 'vPhoneNumbers'-- after the refresh the view returns 4 columns-- this breaks the input/output behavior of the database-- which refactoring MUST NOT doSELECT *FROM vPhoneNumbers -- DoesViewReturnCorrectColumns test will FAIL -- DoesViewReturnCorrectData test will FAIL -- to fix the input/output behavior change problem -- we have to concat the 3 columns into one named PhoneALTER VIEW vPhoneNumbersASSELECT ID, Prefix + ' ' + Number + ' ' + Suffix AS PhoneFROM PhoneNumbersGO-- now it works as expectedSELECT *FROM vPhoneNumbers -- DoesViewReturnCorrectColumns test will SUCCEED -- DoesViewReturnCorrectData test will SUCCEED -- clean upDROP VIEW vPhoneNumbersDROP TABLE PhoneNumbers [Test]public void DoesViewReturnCoorectColumns(){ // conn is a valid SqlConnection to the server's tempdb // note the SET FMTONLY ON with which we return only schema and no data using (SqlCommand cmd = new SqlCommand("SET FMTONLY ON; SELECT * FROM vPhoneNumbers", conn)) { DataTable dt = new DataTable(); dt.Load(cmd.ExecuteReader(CommandBehavior.CloseConnection)); // test returned schema: number of columns, column names and data types Assert.AreEqual(dt.Columns.Count, 2); Assert.AreEqual(dt.Columns[0].Caption, "ID"); Assert.AreEqual(dt.Columns[0].DataType, typeof(int)); Assert.AreEqual(dt.Columns[1].Caption, "Phone"); Assert.AreEqual(dt.Columns[1].DataType, typeof(string)); }} [Test]public void DoesViewReturnCorrectData(){ // conn is a valid SqlConnection to the server's tempdb using (SqlCommand cmd = new SqlCommand("SELECT * FROM vPhoneNumbers", conn)) { DataTable dt = new DataTable(); dt.Load(cmd.ExecuteReader(CommandBehavior.CloseConnection)); // test returned data: number of rows and their values Assert.AreEqual(dt.Rows.Count, 2); Assert.AreEqual(dt.Rows[0]["ID"], 1); Assert.AreEqual(dt.Rows[0]["Phone"], "111 222333 444"); Assert.AreEqual(dt.Rows[1]["ID"], 2); Assert.AreEqual(dt.Rows[1]["Phone"], "555 666777 888"); }}   With this simple example we’ve seen how a very simple schema can cause a lot of problems in the whole application/database system if it doesn’t have tests. Imagine what would happen if some outside process would depend on that view. It would get wrong data and propagate it silently throughout the system. And that is not good. So have tests at least for the crucial parts of your systems. And with that we conclude the Database Testing and Refactoring week at SQL University. Hope you learned something new and enjoy the learning weeks to come. Have fun!

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• Security in Software

  The term security has many meanings based on the context and perspective in which it is used. Security from the perspective of software/system development is the continuous process of maintaining confidentiality, integrity, and availability of a system, sub-system, and system data. This definition at a very high level can be restated as the following: Computer security is a continuous process dealing with confidentiality, integrity, and availability on multiple layers of a system. Key Aspects of Software Security Integrity Confidentiality Availability Integrity within a system is the concept of ensuring only authorized users can only manipulate information through authorized methods and procedures. An example of this can be seen in a simple lead management application.  If the business decided to allow each sales member to only update their own leads in the system and sales managers can update all leads in the system then an integrity violation would occur if a sales member attempted to update someone else’s leads. An integrity violation occurs when a team member attempts to update someone else’s lead because it was not entered by the sales member.  This violates the business rule that leads can only be update by the originating sales member. Confidentiality within a system is the concept of preventing unauthorized access to specific information or tools.  In a perfect world the knowledge of the existence of confidential information/tools would be unknown to all those who do not have access. When this this concept is applied within the context of an application only the authorized information/tools will be available. If we look at the sales lead management system again, leads can only be updated by originating sales members. If we look at this rule then we can say that all sales leads are confidential between the system and the sales person who entered the lead in to the system. The other sales team members would not need to know about the leads let alone need to access it. Availability within a system is the concept of authorized users being able to access the system. A real world example can be seen again from the lead management system. If that system was hosted on a web server then IP restriction can be put in place to limit access to the system based on the requesting IP address. If in this example all of the sales members where accessing the system from the 192.168.1.23 IP address then removing access from all other IPs would be need to ensure that improper access to the system is prevented while approved users can access the system from an authorized location. In essence if the requesting user is not coming from an authorized IP address then the system will appear unavailable to them. This is one way of controlling where a system is accessed. Through the years several design principles have been identified as being beneficial when integrating security aspects into a system. These principles in various combinations allow for a system to achieve the previously defined aspects of security based on generic architectural models. Security Design Principles Least Privilege Fail-Safe Defaults Economy of Mechanism Complete Mediation Open Design Separation Privilege Least Common Mechanism Psychological Acceptability Defense in Depth Least Privilege Design PrincipleThe Least Privilege design principle requires a minimalistic approach to granting user access rights to specific information and tools. Additionally, access rights should be time based as to limit resources access bound to the time needed to complete necessary tasks. The implications of granting access beyond this scope will allow for unnecessary access and the potential for data to be updated out of the approved context. The assigning of access rights will limit system damaging attacks from users whether they are intentional or not. This principle attempts to limit data changes and prevents potential damage from occurring by accident or error by reducing the amount of potential interactions with a resource. Fail-Safe Defaults Design PrincipleThe Fail-Safe Defaults design principle pertains to allowing access to resources based on granted access over access exclusion. This principle is a methodology for allowing resources to be accessed only if explicit access is granted to a user. By default users do not have access to any resources until access has been granted. This approach prevents unauthorized users from gaining access to resource until access is given. Economy of Mechanism Design PrincipleThe Economy of mechanism design principle requires that systems should be designed as simple and small as possible. Design and implementation errors result in unauthorized access to resources that would not be noticed during normal use. Complete Mediation Design PrincipleThe Complete Mediation design principle states that every access to every resource must be validated for authorization. Open Design Design PrincipleThe Open Design Design Principle is a concept that the security of a system and its algorithms should not be dependent on secrecy of its design or implementation Separation Privilege Design PrincipleThe separation privilege design principle requires that all resource approved resource access attempts be granted based on more than a single condition. For example a user should be validated for active status and has access to the specific resource. Least Common Mechanism Design PrincipleThe Least Common Mechanism design principle declares that mechanisms used to access resources should not be shared. Psychological Acceptability Design PrincipleThe Psychological Acceptability design principle refers to security mechanisms not make resources more difficult to access than if the security mechanisms were not present Defense in Depth Design PrincipleThe Defense in Depth design principle is a concept of layering resource access authorization verification in a system reduces the chance of a successful attack. This layered approach to resource authorization requires unauthorized users to circumvent each authorization attempt to gain access to a resource. When designing a system that requires meeting a security quality attribute architects need consider the scope of security needs and the minimum required security qualities. Not every system will need to use all of the basic security design principles but will use one or more in combination based on a company’s and architect’s threshold for system security because the existence of security in an application adds an additional layer to the overall system and can affect performance. That is why the definition of minimum security acceptably is need when a system is design because this quality attributes needs to be factored in with the other system quality attributes so that the system in question adheres to all qualities based on the priorities of the qualities. Resources: Barnum, Sean. Gegick, Michael. (2005). Least Privilege. Retrieved on August 28, 2011 from https://buildsecurityin.us-cert.gov/bsi/articles/knowledge/principles/351-BSI.html Saltzer, Jerry. (2011). BASIC PRINCIPLES OF INFORMATION PROTECTION. Retrieved on August 28, 2011 from  http://web.mit.edu/Saltzer/www/publications/protection/Basic.html Barnum, Sean. Gegick, Michael. (2005). Defense in Depth. Retrieved on August 28, 2011 from  https://buildsecurityin.us-cert.gov/bsi/articles/knowledge/principles/347-BSI.html Bertino, Elisa. (2005). Design Principles for Security. Retrieved on August 28, 2011 from  http://homes.cerias.purdue.edu/~bhargav/cs526/security-9.pdf

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• how to reinstall/repair ubuntu 12.04 after dual boot installation fails with windows 7

  - by Rini

  I have installed Ubuntu 12.04 on my preinstalled windows 7 Sony vaio s series laptop following instructions here: http://www.linuxbsdos.com/2012/05/17/how-to-dual-boot-ubuntu-12-04-and-windows-7/ Everything went well and I am able to boot in to windows after complete installation of Ubuntu. Now following instructions on web I tried to add Ubuntu to my BIOS using Easy BCD (but forget to add windows 7 entry). As a result, I loose windows 7 OS and can't boot in to either OS then I successfully repaired windows 7 using recovery CD. Now my problem is that I can't reinstall Ubuntu 12.04 using Live CD it halts every time before disk partition step giving error. "ubi-partman crashed". "ubi-partman failed with exit code 141. further information may be found in /var/log/syslog. Do you want to try running this step again before continuing? If you do not, your installation may fail entirely or may be broken." and, any choice to continue will result in the same error. I looked in to /var/log/syslog but not able to understand what is error. Then, I ran sudo fdisk -l to view my partitions and it shows me only one partition. Probably, all the partitions I created for Ubuntu 12.04 are lost while running windows 7 recovery CD. So, I don't know whether the Ubuntu is still there or probably corrupted. My boot-info URL is: http://paste.ubuntu.com/1202146/ Please tell me how to remove this error so that I can reinstall/repair Ubuntu 12.04 Thanks in advance. R Shukla My boot-info URL is: http://paste.ubuntu.com/1202146/ Please tell me how to remove this error so that I can reinstall/repair Ubuntu 12.04 Thanks for your help! I tried to boot from the CD but I every time it give me error before disk partitioning step. Also, I am unable to start Gparted. "ubi-partman crashed". "ubi-partman failed with exit code 141. further information may be found in /var/log/syslog. Do you want to try running this step again before continuing? If you do not, your installation may fail entirely or may be broken." and, any choice to continue will result in the same error. I looked in to /var/log/syslog but not able to understand what is error. Then, I ran sudo fdisk -l to view my partitions and it shows me only ne partition. Probaply, all the partitions I created for Ubuntu 12.04 are lost while running windows 7 recovery CD. Please tell me how to remove this error. Best Regards, R S

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• Forget Page Rank - Readers Are Far More Long Term

  For a blog or website to succeed you need more than just a good Page Rank - you need a loyal following of readers. If you concentrate only on building your Page Rank, you are building your website to fail. Instead, bear in mind ways of increasing your readership.

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• What's the best book for coding conventions?

  - by Joschua

  What's the best book about coding conventions (and perhaps design patterns), that you highly recommend (at best code samples in Python, C++ or Java)? It would be good, if the book (or just another) also covers the topics project management and agile software development if appropriate (for example how projects fail through spaghetti code). I will accept the answer with the book(s) (maximum two books per answer, please), that looks the most interesting, because the reading might take a while :)

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• Master database Compatibility level after an In-place Upgrade

  - by Jonathan Kehayias

  Yesterday a forums member asked why sys.dm_exec_sql_text() wouldn’t work on one instance of SQL where he was a sysadmin while the same code worked correctly on another instance of SQL.  The initial thought was that it was some kind of permissions issue.  Ken Simmons ( blog / twitter ) pointed out that the compatibility level of the database would affect the ability to use this DMF and that running it from a database at 80 compatibility would fail.  It turns out the person was running...(read more)

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• Test interface implementation

  - by Michael

  I have a interface in our code base that I would like to be able to mock out for unit testing. I am writing a test implementation to allow the individual tests to be able to override the specific methods they are concerned with rather than implementing every method. I've run into a quandary over how the test implementation should behave if the test fails to override a method used by the method under test. Should I return a "non-value" (0, null) in the test implementation or throw a UnsupportedOperationException to explicitly fail the test?

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• Lubuntu: neither shut-down nor restart works

  - by Rantanplan

  aI have a freshly installed Lubuntu 14.04.1 (installed with forcepae option on a laptop with Pentium M processor). The only problem that I have found so far is that I cannot shut-down or restart the laptop. It always continues showing "Lubuntu" and some dots. Pressing Esc it says wait-for-state stop/waiting * Stopping rsync daemon rsync [OK] * Asking all remaining processes to terminate… [OK] * Killing all remaining processes… [fail] ModemManager [597] : <info> Caught signal, shutting down… ModemManager [597] : <info> ModemManager is shut down nm-dispatcher.action: Could not get the system bus. Make sure the message bus daemon is running! Message: Did not receive a reply. Possible causes: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken. * Deactivating swap… [OK] * Will now halt The cursor remains blinking but the only way to switch it off is to hold the power-off key pressed for some seconds. I tried sudo shutdown -h now, sudo halt and sudo poweroff resulting in the same problem. I also tried to add acpi=force in GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" in /etc/default/grub and run sudo update-grub; then, using the taskbar's shot-down button lead to a direct stop of the laptop equal to holding the power-off key pressed for some seconds. Next I followed the answer http://askubuntu.com/a/202481/288322. Now, I directly receive some messages during shut-down starting wait-for-state stop/waiting * Stopping rsync daemon rsync [OK] * Asking all remaining processes to terminate… [OK] [ 240.944277] INFO: task kworker/0:2:24: block for more than 120 seconds. [ 240.944461] Tainted: G S 3.13.0-34-generic #60-Ubuntu [ 240.944623] "echo 0 > /proc/sys/kernel/hung_tasks_timeout_secs" disables this message. followed by some more similar lines and then: * Killing all remaining processes… [fail] ModemManager [576] : <info> Caught signal, shutting down… nm-dispatcher.action: Caught signal 15, shutting down... ModemManager [576] : <info> ModemManager is shut down * Deactivating swap… [OK] * Will now halt [ 600.944276] INFO: task kworker/0:2:24: block for more than 120 seconds. [ 600.944458] Tainted: G S 3.13.0-34-generic #60-Ubuntu [ 600.944619] "echo 0 > /proc/sys/kernel/hung_tasks_timeout_secs" disables this message. Then, nothing more was coming during the next 5 minutes. If you know where can I find relevant error information, I will be happy to search for them.

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• How to Tell a Hardware Problem From a Software Problem

  - by Chris Hoffman

  Your computer seems to be malfunctioning — it’s slow, programs are crashing or Windows may be blue-screening. Is your computer’s hardware failing, or does it have a software problem that you can fix on your own? This can actually be a bit tricky to figure out. Hardware problems and software problems can lead to the same symptoms — for example, frequent blue screens of death may be caused by either software or hardware problems. Computer is Slow We’ve all heard the stories — someone’s computer slows down over time because they install too much software that runs at startup or it becomes infected with malware. The person concludes that their computer is slowing down because it’s old, so they replace it. But they’re wrong. If a computer is slowing down, it has a software problem that can be fixed. Hardware problems shouldn’t cause your computer to slow down. There are some rare exceptions to this — perhaps your CPU is overheating and it’s downclocking itself, running slower to stay cooler — but most slowness is caused by software issues. Blue Screens Modern versions of Windows are much more stable than older versions of Windows. When used with reliable hardware with well-programmed drivers, a typical Windows computer shouldn’t blue-screen at all. If you are encountering frequent blue screens of death, there’s a good chance your computer’s hardware is failing. Blue screens could also be caused by badly programmed hardware drivers, however. If you just installed or upgraded hardware drivers and blue screens start, try uninstalling the drivers or using system restore — there may be something wrong with the drivers. If you haven’t done anything with your drivers recently and blue screens start, there’s a very good chance you have a hardware problem. Computer Won’t Boot If your computer won’t boot, you could have either a software problem or a hardware problem. Is Windows attempting to boot and failing part-way through the boot process, or does the computer no longer recognize its hard drive or not power on at all? Consult our guide to troubleshooting boot problems for more information. When Hardware Starts to Fail… Here are some common components that can fail and the problems their failures may cause: Hard Drive: If your hard drive starts failing, files on your hard drive may become corrupted. You may see long delays when you attempt to access files or save to the hard drive. Windows may stop booting entirely. CPU: A failing CPU may result in your computer not booting at all. If the CPU is overheating, your computer may blue-screen when it’s under load — for example, when you’re playing a demanding game or encoding video. RAM: Applications write data to your RAM and use it for short-term storage. If your RAM starts failing, an application may write data to part of the RAM, then later read it back and get an incorrect value. This can result in application crashes, blue screens, and file corruption. Graphics Card: Graphics card problems may result in graphical errors while rendering 3D content or even just while displaying your desktop. If the graphics card is overheating, it may crash your graphics driver or cause your computer to freeze while under load — for example, when playing demanding 3D games. Fans: If any of the fans fail in your computer, components may overheat and you may see the above CPU or graphics card problems. Your computer may also shut itself down abruptly so it doesn’t overheat any further and damage itself. Motherboard: Motherboard problems can be extremely tough to diagnose. You may see occasional blue screens or similar problems. Power Supply: A malfunctioning power supply is also tough to diagnose — it may deliver too much power to a component, damaging it and causing it to malfunction. If the power supply dies completely, your computer won’t power on and nothing will happen when you press the power button. Other common problems — for example, a computer slowing down — are likely to be software problems. It’s also possible that software problems can cause many of the above symptoms — malware that hooks deep into the Windows kernel can cause your computer to blue-screen, for example. The Only Way to Know For Sure We’ve tried to give you some idea of the difference between common software problems and hardware problems with the above examples. But it’s often tough to know for sure, and troubleshooting is usually a trial-and-error process. This is especially true if you have an intermittent problem, such as your computer blue-screening a few times a week. You can try scanning your computer for malware and running System Restore to restore your computer’s system software back to its previous working state, but these aren’t  guaranteed ways to fix software problems. The best way to determine whether the problem you have is a software or hardware one is to bite the bullet and restore your computer’s software back to its default state. That means reinstalling Windows or using the Refresh or reset feature on Windows 8. See whether the problem still persists after you restore its operating system to its default state. If you still see the same problem – for example, if your computer is blue-screening and continues to blue-screen after reinstalling Windows — you know you have a hardware problem and need to have your computer fixed or replaced. If the computer crashes or freezes while reinstalling Windows, you definitely have a hardware problem. Even this isn’t a completely perfect method — for example, you may reinstall Windows and install the same hardware drivers afterwards. If the hardware drivers are badly programmed, the blue-screens may continue. Blue screens of death aren’t as common on Windows these days — if you’re encountering them frequently, you likely have a hardware problem. Most blue screens you encounter will likely be caused by hardware issues. On the other hand, other common complaints like “my computer has slowed down” are easily fixable software problems. When in doubt, back up your files and reinstall Windows. Image Credit: Anders Sandberg on Flickr, comedy_nose on Flickr     

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• Need a Better Cleanup Tool [Humorous Image]

  - by Asian Angel

  Obviously some cleanup tools work better than others…and sometimes common sense cleanup is the best tool of all! Note: Notice the timeline in the image… View the Full-Size Version of the Image Got a sales guys laptop back… Note the times. [via Fail Desk] The Best Free Portable Apps for Your Flash Drive Toolkit How to Own Your Own Website (Even If You Can’t Build One) Pt 3 How to Sync Your Media Across Your Entire House with XBMC

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