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  • SQL Server 2008 R2 Enterprise won't install on Windows 2008 R2 Enterprise

    - by Carlos Paulino
    I've been trying to install SQL Server on a new Windows Server 2008. I have tried everything but I haven't been able to narrow down the problem. When the installation fails I get " Exit code (Decimal): -2068643839". The problem with this is that according to Microsoft this is a generic error code. I follow their guide to look into the detail.txt inside C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\ But I can't find something that specifies the exact error. Any suggestions ? Thanks in advanced. I uploaded to detail.txt to http://www.megaupload.com/?d=0MV46SZH because it is to big to paste here. Below is the summary.txt ---------- Overall summary: Final result: SQL Server installation failed. To continue, investigate the reason for the failure, correct the problem, uninstall SQL Server, and then rerun SQL Server Setup. Exit code (Decimal): -2068643839 Exit facility code: 1203 Exit error code: 1 Exit message: SQL Server installation failed. To continue, investigate the reason for the failure, correct the problem, uninstall SQL Server, and then rerun SQL Server Setup. Start time: 2011-02-28 11:29:56 End time: 2011-02-28 11:34:45 Requested action: Install Machine Properties: Machine name: SA-SERVER Machine processor count: 8 OS version: Windows Server 2008 R2 OS service pack: Service Pack 1 OS region: United States OS language: English (United States) OS architecture: x64 Process architecture: 64 Bit OS clustered: No Product features discovered: Product Instance Instance ID Feature Language Edition Version Clustered Package properties: Description: SQL Server Database Services 2008 R2 ProductName: SQL Server 2008 R2 Type: RTM Version: 10 SPLevel: 0 Installation location: F:\x64\setup\ Installation edition: ENTERPRISE User Input Settings: ACTION: Install ADDCURRENTUSERASSQLADMIN: True AGTSVCACCOUNT: NT AUTHORITY\SYSTEM AGTSVCPASSWORD: ***** AGTSVCSTARTUPTYPE: Manual ASBACKUPDIR: Backup ASCOLLATION: Latin1_General_CI_AS ASCONFIGDIR: Config ASDATADIR: Data ASDOMAINGROUP: <empty> ASLOGDIR: Log ASPROVIDERMSOLAP: 1 ASSVCACCOUNT: <empty> ASSVCPASSWORD: ***** ASSVCSTARTUPTYPE: Automatic ASSYSADMINACCOUNTS: <empty> ASTEMPDIR: Temp BROWSERSVCSTARTUPTYPE: Disabled CONFIGURATIONFILE: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20110228_112601\ConfigurationFile.ini CUSOURCE: ENABLERANU: False ENU: True ERRORREPORTING: False FARMACCOUNT: <empty> FARMADMINPORT: 0 FARMPASSWORD: ***** FEATURES: SQLENGINE,BIDS,CONN,IS,BC,SDK,SSMS,ADV_SSMS,SNAC_SDK,OCS FILESTREAMLEVEL: 0 FILESTREAMSHARENAME: <empty> FTSVCACCOUNT: <empty> FTSVCPASSWORD: ***** HELP: False IACCEPTSQLSERVERLICENSETERMS: False INDICATEPROGRESS: False INSTALLSHAREDDIR: C:\Program Files\Microsoft SQL Server\ INSTALLSHAREDWOWDIR: C:\Program Files (x86)\Microsoft SQL Server\ INSTALLSQLDATADIR: <empty> INSTANCEDIR: D:\SQLServer INSTANCEID: MSSQLSERVER INSTANCENAME: MSSQLSERVER ISSVCACCOUNT: NT AUTHORITY\SYSTEM ISSVCPASSWORD: ***** ISSVCSTARTUPTYPE: Automatic NPENABLED: 0 PASSPHRASE: ***** PCUSOURCE: PID: ***** QUIET: False QUIETSIMPLE: False ROLE: AllFeatures_WithDefaults RSINSTALLMODE: FilesOnlyMode RSSVCACCOUNT: NT AUTHORITY\NETWORK SERVICE RSSVCPASSWORD: ***** RSSVCSTARTUPTYPE: Automatic SAPWD: ***** SECURITYMODE: SQL SQLBACKUPDIR: <empty> SQLCOLLATION: SQL_Latin1_General_CP1_CI_AS SQLSVCACCOUNT: NT AUTHORITY\SYSTEM SQLSVCPASSWORD: ***** SQLSVCSTARTUPTYPE: Automatic SQLSYSADMINACCOUNTS: SA-SERVER\Administrator SQLTEMPDBDIR: <empty> SQLTEMPDBLOGDIR: <empty> SQLUSERDBDIR: <empty> SQLUSERDBLOGDIR: <empty> SQMREPORTING: False TCPENABLED: 1 UIMODE: Normal X86: False Configuration file: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20110228_112601\ConfigurationFile.ini Detailed results: Feature: Database Engine Services Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: SQL Client Connectivity SDK Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: Integration Services Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: Client Tools Connectivity Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: Management Tools - Complete Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: Management Tools - Basic Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: Client Tools SDK Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: Client Tools Backwards Compatibility Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: Business Intelligence Development Studio Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Feature: Microsoft Sync Framework Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Rules with failures: Global rules: Scenario specific rules: Rules report file: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20110228_112601\SystemConfigurationCheck_Report.htm

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  • Configuring Cisco 877W router from scratch for DHCP, WiFi, ADSL2+, NAT

    - by David M Williams
    Hi all, I apologise if this is a BIG question but I am quite lost with the Cisco IOS. I know what I want to achieve just not how to do it :( I have a Cisco 877W router with 4 FastEthernet interfaces, 1 ATM interface and 1 802.11 Radio. I want to set it up for a small network and am trying to construct a configuration below. I was using Google to try and flesh it out but I think I need help and guidance from actual experts! If it helps, output from show ver says Cisco IOS software, C870 software (C870-ADVSECURITYK9-M), version 12.4(4)T7, release software (fc1) ROM: System bootstrap, version 12.3(8r)YI4, release software Here's what I have so far, which hopefully outlines clearly enough what I am wanting to do. The bits in angle brackets are placeholders (eg the secret password). ! ! Set router hostname ! hostname Shazam ! ! Set usernames and passwords ! username david privilege 15 secret 0 <PASSWORD> enable secret <SECRETPASSWORD> ! ! Configure SSH and telnet access ! line vty 0 4 privilege level 15 login local transport input telnet ssh ! ! Local logging ! logging buffered 51200 warning ! ! Set date and time for NSW, Australia (GMT +10h) ! ! ! Set router IP address to 192.168.1.1 on FastEthernet0 port ! interface FastEthernet0 ip address 192.168.1.1 255.255.255.0 no shut ip nat inside ! ! Forward any unknown DNS requests to Google ! ip dns server ip name-server 8.8.8.8 ip name-server 8.8.4.4 ! ! Set up DHCP ! DHCP pool covers 192.168.1.100 - .199 ! Set gateway and DNS server to be the router, ie 192.168.1.1 ! service dhcp ip routing ip dhcp excluded-address 192.168.1.1 192.168.1.99 ip dhcp excluded-address 192.168.1.200 192.168.1.255 ip dhcp pool <DHCPPOOLNAME> network 192.168.1.0 255.255.255.0 default-router 192.168.1.1 dns-server 192.168.1.1 lease 7 ! ! DHCP reservations ! ! Assign IP address 192.168.1.105 to MAC address 00-21-5D-2F-58-04 ! ! Configure ADSL2 connection details ! interface atm dsl operating-mode adsl2+ ! ! Set up NAT rules ! ! Forward port 35394 to 192.168.1.105 ! ! Set up WiFi ! ! SSID visible, WPA2 security, Pre-shared key I'm hoping most of this is boiler-plate stuff to you guys. I'm keen to not just get a working script but to actually understand it also. Unfortunately, I'm finding the Cisco reference material online very complex. Thank you!

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  • apache eat up too many ram per child

    - by mrc4r7m4n
    Hello to everyone. I've got fallowing problem: Apache eat to many ram per child. The fallowing comments shows: cat /etc/redhat-release -- Fedora release 8 (Werewolf) free -m: total used free shared buffers cached Mem: 3566 3136 429 0 339 1907 -/+ buffers/cache: 889 2676 Swap: 4322 0 4322 I know that you will say that there is nothing to worry about because swap is not use, but i think it's not use for now. 3.httpd -v: Server version: Apache/2.2.14 (Unix) 4.httpd -l: Compiled in modules: core.c mod_authn_file.c mod_authn_default.c mod_authz_host.c mod_authz_groupfile.c mod_authz_user.c mod_authz_default.c mod_auth_basic.c mod_include.c mod_filter.c mod_log_config.c mod_env.c mod_setenvif.c mod_version.c mod_ssl.c prefork.c http_core.c mod_mime.c mod_status.c mod_autoindex.c mod_asis.c mod_cgi.c mod_negotiation.c mod_dir.c mod_actions.c mod_userdir.c mod_alias.c mod_rewrite.c mod_so.c 5.List of loaded dynamic modules: LoadModule authz_host_module modules/mod_authz_host.so LoadModule include_module modules/mod_include.so LoadModule log_config_module modules/mod_log_config.so LoadModule setenvif_module modules/mod_setenvif.so LoadModule mime_module modules/mod_mime.so LoadModule autoindex_module modules/mod_autoindex.so LoadModule vhost_alias_module modules/mod_vhost_alias.so LoadModule negotiation_module modules/mod_negotiation.so LoadModule dir_module modules/mod_dir.so LoadModule alias_module modules/mod_alias.so LoadModule rewrite_module modules/mod_rewrite.so LoadModule proxy_module modules/mod_proxy.so LoadModule cgi_module modules/mod_cgi.so 6.My prefrok directive <IfModule prefork.c> StartServers 8 MinSpareServers 5 MaxSpareServers 25 ServerLimit 80 MaxClients 80 MaxRequestsPerChild 4000 </IfModule> KeepAliveTimeout 6 MaxKeepAliveRequests 100 KeepAlive On 7.top -u apache: ctrl+ M top - 09:19:42 up 2 days, 19 min, 2 users, load average: 0.85, 0.87, 0.80 Tasks: 113 total, 1 running, 112 sleeping, 0 stopped, 0 zombie Cpu(s): 7.3%us, 15.7%sy, 0.0%ni, 75.7%id, 0.0%wa, 0.7%hi, 0.7%si, 0.0%st Mem: 3652120k total, 3149964k used, 502156k free, 348048k buffers Swap: 4425896k total, 0k used, 4425896k free, 1944952k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 16956 apache 20 0 700m 135m 100m S 0.0 3.8 2:16.78 httpd 16953 apache 20 0 565m 130m 96m S 0.0 3.7 1:57.26 httpd 16957 apache 20 0 587m 129m 102m S 0.0 3.6 1:47.41 httpd 16955 apache 20 0 567m 126m 93m S 0.0 3.6 1:43.60 httpd 17494 apache 20 0 626m 125m 96m S 0.0 3.5 1:58.77 httpd 17515 apache 20 0 540m 120m 88m S 0.0 3.4 1:45.57 httpd 17516 apache 20 0 573m 120m 88m S 0.0 3.4 1:50.51 httpd 16954 apache 20 0 551m 120m 88m S 0.0 3.4 1:52.47 httpd 17493 apache 20 0 586m 120m 94m S 0.0 3.4 1:51.02 httpd 17279 apache 20 0 568m 117m 87m S 16.0 3.3 1:51.87 httpd 17302 apache 20 0 560m 116m 90m S 0.3 3.3 1:59.06 httpd 17495 apache 20 0 551m 116m 89m S 0.0 3.3 1:47.51 httpd 17277 apache 20 0 476m 114m 81m S 0.0 3.2 1:37.14 httpd 30097 apache 20 0 536m 113m 83m S 0.0 3.2 1:47.38 httpd 30112 apache 20 0 530m 112m 81m S 0.0 3.2 1:40.15 httpd 17513 apache 20 0 516m 112m 85m S 0.0 3.1 1:43.92 httpd 16958 apache 20 0 554m 111m 82m S 0.0 3.1 1:44.18 httpd 1617 apache 20 0 487m 111m 85m S 0.0 3.1 1:31.67 httpd 16952 apache 20 0 461m 107m 75m S 0.0 3.0 1:13.71 httpd 16951 apache 20 0 462m 103m 76m S 0.0 2.9 1:28.05 httpd 17278 apache 20 0 497m 103m 76m S 0.0 2.9 1:31.25 httpd 17403 apache 20 0 537m 102m 79m S 0.0 2.9 1:52.24 httpd 25081 apache 20 0 412m 101m 70m S 0.0 2.8 1:01.74 httpd I guess thats all information needed to help me solve this problem. I think the virt memory is to big, the same res. The consumption of ram is increasing all the time. Maybe it's memory leak because i see there is so many static modules compiled. Could someone help me with this issue? Thank you in advance.

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  • SSL certificates and types for securing your websites and applications

    - by Mit Naik
    Need to share few information regarding SSL certificates and there types, which SSL certificates are widely used etc. There are several SSL certificates available in the market today inorder to secure your domains, multiple subdomains, your applications and code too. Few of the details are mentioned below. CheapSSL certificates available today are Standard Rapidssl certificate, Thwate SSL 123 etc certificates which are basic level certificates. Most of these cheap SSL certificates are domain-validated only and don't provide the greatest trust for your customers. This means you shouldn't use cheap SSL certificates on e-commerce stores or other public-facing sites that require people to trust the site. EV certificates I found Geotrust Truebusinessid with EV certificate which is one of the cheapest certificate available in market today, you can also find Thwate, Versign EV version of certificates. Its designed to prevent phishing attacks better than normal SSL certificates. What makes an EV Certificate so special? An SSL Certificate Provider has to do some extensive validation to give you one including: Verifying that your organization is legally registered and active, Verifying the address and phone number of your organization, Verifying that your organization has exclusive right to use the domain specified in the EV Certificate, Verifying that the person ordering the certificate has been authorized by the organization, Verifying that your organization is not on any government blacklists. SSL WILDCARD CERTIFICATES, SSL Wildcard Certificates are big money-savers. An SSL Wildcard Certificate allows you to secure an unlimited number of first-level sub-domains on a single domain name. For example, if you need to secure the following websites: * www.yourdomain.com * secure.yourdomain.com * product.yourdomain.com * info.yourdomain.com * download.yourdomain.com * anything.yourdomain.com and all of these websites are hosted on the multiple server box, you can purchase and install one Wildcard certificate issued to *.yourdomain.com to secure all these sites. SAN CERTIFICATES, are interesting certificates and are helpfull if you want to secure multiple domains by generating single CSR and can install the same certificate on your additional sites without generating new CSRs for all the additional domains. CODE SIGNING CERTIFICATES, A code signing certificate is a file containing a digital signature that can be used to sign executables and scripts in order to verify your identity and ensure that your code has not been tampered with since it was signed. This helps your users to determine whether your software can be trusted. Scroll to the chart below to compare cheap code signing certificates. A code signing certificate allows you to sign code using a private and public key system similar to how an SSL certificate secures a website. When you request a code signing certificate, a public/private key pair is generated. The certificate authority will then issue a code signing certificate that contains the public key. A certificate for code signing needs to be signed by a trusted certificate authority so that the operating system knows that your identity has been validated. You could still use the code signing certificate to sign and distribute malicious software but you will be held legally accountable for it. You can sign many different types of code. The most common types include Windows applications such as .exe, .cab, .dll, .ocx, and .xpi files (using an Authenticode certificate), Apple applications (using an Apple code signing certificate), Microsoft Office VBA objects and macros (using a VBA code signing certificate), .jar files (using a Java code signing certificate), .air or .airi files (using an Adobe AIR certificate), and Windows Vista drivers and other kernel-mode software (using a Vista code certificate). In reality, a code signing certificate can sign almost all types of code as long as you convert the certificate to the correct format first. Also I found the below URL which provides you good suggestion regarding purchasing best SSL certificates for securing your site, as per the Financial institution, Bank, Hosting providers, ISP, Retail Merchants etc. Please vote and provide comments or any additional suggestions regarding SSL certificates.

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  • Useful software for netbook?

    - by Moayad Mardini
    I'm looking for recommendations of good software that are particularly useful for netbooks. Software that run great on small screens and low CPU/RAM requirments. I'll start off with the following : Operating Systems: Ubuntu Netbook Remix. Easy Peasy: A fork of Ubuntu Netbook Remix that was once called UBuntu EEE. It isn't just for eeePCs though. Definitely worth a look if vanilla Netbook Remix isn't cutting it. (MarkM) Damn Small Linux (Source) Windows 7: With trimming the installation or compressing the Windows directory to fit on an 8GB SSD. (Will Eddins) nLite: A utility to install a lightweight version of Windows XP without the unnecessary components (like Media Player, Internet Explorer, Outlook Express, MSN Explorer, Messenger...). Utilites: TouchFreeze: To disable the touch pad while typing (Source) InSSIDer: Not only does it make it easier to find and keep a wireless connection, but it turns a netbook into the perfect mobile tool for troubleshooting wireless networks. (phenry) AltMove: Adds more functionality to your mouse for interacting with windows. (Rob) ASUS Font Resizer Utility and other tools by ASUS, specific to ASUS Eee PC series. Internet: Run FileZilla FTP client for a small screen : You can hide a lot of FileZilla's interface parts in the View menu, even the directory trees. Go into Settings = Interface and move the message log next to the transfer queue, if you haven't hidden them both or you want to see them. Select a theme with 16x16 icons. (Source) IDEs and Text Editors: Best lightweight IDE/Text Editor: A question on Stack Overflow that has many good suggestions of IDEs and general text editors for programmers. What’s a good linux C/C++ IDE for a low-res screen?: IDEs for Linux-powered netbooks. Online tools: Dropbox: Since the Netbook has limited disk space, you would like to use Cloud Apps like Dropbox and Ubuntu One so that you don't run out of space especially if you are on a holiday. Later when you go back to your desktop with big hard disk,you can take out the files from your dropbox repo. (Manish Sinha) Google products: like Docs, Calendar and Reader (aviraldg) Web sites and software lists: Netbookfiles.com: Netbook specific software downloads. Software Apps to Maximise your Netbook Battery Power: Netbooks are known for their portability. Not only are they small and lightweight but with their increased power efficiency, batteries can last much longer than conventional laptops. This also means you no longer have to carry a power adapter with you! Several brands emphasis the longevity of the battery as a strong selling point, and for those people who travel a lot, it sure is. Free Must-Have Netbook Apps: Finding software for netbooks can present challenges due to limited hard drive space, processor power, RAM, and screen real-estate. That doesn't mean you have to do without essential programs. The apps below cover all the bases -- entertainment, productivity, security, and communication -- without compromising on performance or usability. Best of all, they're free! Useful Netbook Software: With short battery lives and small resolution screens Netbooks, unlike many other computers on the market, could so with some specific software for their use. Now, not all of those I’ve found are specifically designed for Netbooks, but all are relevant. And they’re designed for Windows XP. The question is community wiki, so feel free to edit it. Updated, thank you all for suggestions.

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  • Is there really a need for encryption to have true wireless security? [closed]

    - by Cawas
    I welcome better key-wording here, both on tags and title. I'm trying to conceive a free, open and secure network environment that would work anywhere, from big enterprises to small home networks of just 1 machine. I think since wireless Access Points are the most, if not only, true weak point of a Local Area Network (let's not consider every other security aspect of having internet) there would be basically two points to consider here: Having an open AP for anyone to use the internet through Leaving the whole LAN also open for guests to be able to easily read (only) files on it, and even a place to drop files on Considering these two aspects, once everything is done properly... What's the most secure option between having that, or having just an encrypted password-protected wifi? Of course "both" would seem "more secure". But it shouldn't actually be anything substantial. That's the question, but I think it may need more elaborating on. If you don't think so, please feel free to skip the next (long) part. Elaborating more on the two aspects ... I've always had the feeling using any kind of the so called "wireless security" methods is actually a bad design. I'm talking mostly about encrypting and pass-phrasing (which are actually two different concepts), since I won't even consider hiding SSID and mac filtering. I understand it's a natural way of thinking. With cable networking nobody can access the network unless they have access to the physical cable, so you're "secure" in the physical way. In a way, encrypting is for wireless what building walls is for the cables. And giving pass-phrases would be adding a door with a key. But the cabling without encryption is also insecure. If someone plugin all the data is right there. So, while I can see the use for encrypting data, I don't think it's a security measure in wireless networks. It's wasting resources for too little gain. I believe we should encrypt only sensitive data regardless of wires. That's already done with HTTPS, so I don't really need to encrypt my torrents, for instance. They're torrents, they are meant to be freely shared! As for using passwords, they should be added to the users, always. Not to wifi. For securing files, truly, best solution is backup. Sure all that doesn't happen that often, but I won't consider the most situations where people just don't care. I think there are enough situations where we actually use passwords on our OS users, so let's go with that in mind. I keep promoting the Fonera concept as an instance. It opens up a free wifi port, if you choose so, and anyone can connect to the internet through that, without having any access to your LAN. It also uses a QoS which will never let your bandwidth drop from that public usage. That's security, and it's open. But it's lacking the second aspect. I'll probably be bashed for promoting the non-usage of WPA 2 with AES or whatever, but I wanted to know from more experienced (super) users out there: what do you think?

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  • ubuntu wifi disconnection & frustratingly connects to unavailable wifi

    - by ashishsony
    Hi, i have already posted this here: here This has happened before with ubuntu 9.1 Beta2 build too that my wifi disconnects if im idle for 5 minutes... so i cant leave my lappy to download anything... i have to keep on continuously using it.. as soon i leave it idle for abt 5 minutes... wifi disconnects... and the pop up asking for password for wifi pops up...with the password already filled in... i just click on connect and it connects again... so whats the use of asking the password if the pre filled in pass works correctly... and this is happening on ubuntu 10.04 Beta2 too... and the workaround is that just open any menu like the applications menu in the taskbar and keep it open... under this state the ubuntu idleness never activates and so the wifi gets never disconnected... this has been confirmed by me many times.. this seems to be repeating again and again... i dont know why... and the second thing i want to report is that there is no way to report this bug from ubuntu... the launchpad.net talks of going through bug reporting process which is done against a definite package... now how does a user know which package would be causing this error?? there should be a more clear process of reporting such bugs to ubuntu team... thirdly the apport utility that reports crashing apps is totally uselss on 10.04 beta 2... as it collests information and reports that i cant submit the report because i dont have 100 other packages... without updating which i cant submit the report.... surely on a beta build there would be packages continuously being updated... so no system would be reported as fully updated... and so no practical apport reporting is possible?? please address these issues... really frustrating all this ... im a big fan of ubuntu but these things really bug me... and just to add fourthly... the suspend/hibernate feature has never ever worked on my toshiba m70-113 laptop... on any ubuntu version... always have to hard reboot after putting into suspend/hibernate mode.. on windows this has never been the case... why cant ubuntu beat windows in such cases too?? i would really like to see this soon... most importantly, when the router switches off... the wifi signals go off... then why the hell ubuntu keeps on connecting to that very wifi like hell and when doesnt connect shows the prompt to manually connect... with the wifi key already filled in... whats the use of saving the key when it has to ask the question from me either to connect or not?? and if its isnt available... just wait when its available.. i have only option to cancel and if i cancel it wont auto-connect!! what the heck?? one can see in the image that it says "authentication required by wireless network" when there isnt any.. as router has gone down!!

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  • Oracle performance problem

    - by jreid42
    We are using an Oracle 11G machine that is very powerful; has redundant storage etc. It's a beast from what I have been told. We just got this DB for a tool that when I first came on as a coop had like 20 people using, now its upwards of 150 people. I am the only one working on it :( We currently have a system in place that distributes PERL scripts across our entire data center essentially giving us a sort of "grid" computing power. The Perl scripts run a sort of simulation and report back the results to the database. They do selects / inserts. The load is not very high for each script but it could be happening across 20-50 systems at the same time. We then have multiple data centers and users all hitting the same database with this same approach. Our main problem with this is that our database is getting overloaded with connections and having to drop some. We sometimes have upwards of 500 connections. These are old perl scripts and they do not handle this well. Essentially they fail and the results are lost. I would rather avoid having to rewrite a lot of these as they are poorly written, and are a headache to even look at. The database itself is not overloaded, just the connection overhead is too high. We open a connection, make a quick query and then drop the connection. Very short connections but many of them. The database team has basically said we need to lower the number of connections or they are going to ignore us. Because this is distributed across our farm we cant implement persistent connections. I do this with our webserver; but its on a fixed system. The other ones are perl scripts that get opened and closed by the distribution tool and thus arent always running. What would be my best approach to resolving this issue? The scripts themselves can wait for a connection to be open. They do not need to act immediately. Some sort of queing system? I've been suggested to set up a few instances of a tool called "SQL Relay". Maybe one in each data center. How reliable is this tool? How good is this approach? Would it work for what we need? We could have one for each data center and relay requests through it to our main database, keeping a pipeline of open persistent connections? Does this make sense? Is there any other suggestions you can make? Any ideas? Any help would be greatly appreciated. Sadly I am just a coop student working for a very big company and somehow all of this has landed all on my shoulders (there is literally nobody to ask for help; its a hardware company, everybody is hardware engineers, and the database team is useless and in India) and I am quite lost as what the best approach would be? I am extremely overworked and this problem is interfering with on going progress and basically needs to be resolved as quickly as possible; preferably without rewriting the whole system, purchasing hardware (not gonna happen), or shooting myself in the foot. HELP LOL!

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  • I want to change DPI with Imagemagick without changing the actual byte-size of the image data

    - by user1694803
    I feel so horribly sorry that I have to ask this question here, but after hours of researching how to do an actually very simple task I'm still failing... In Gimp there is a very simple way to do what I want. I only have the German dialog installed but I'll try to translate it. I'm talking about going to "Picture-PrintingSize" and then adjusting the Values "X-Resolution" and "Y-Resolution" which are known to me as so called DPI values. You can also choose the format which by default is "Pixel/Inch". (In German the dialog is "Bild-Druckgröße" and there "X-Auflösung" and "Y-Auflösung") Ok, the values there are often "72" by default. When I change them to e.g. "300" this has the effect that the image stays the same on the computer, but if I print it, it will be smaller if you look at it, but all the details are still there, just smaller - it has a higher resolution on the printed paper (but smaller size... which is fine for me). I am often doing that when I am working with LaTeX, or to be exact with the command "pdflatex" on a recent Ubuntu-Machine. When I'm doing the above process with Gimp manually everything works just fine. The images will appear smaller in the resulting PDF but with high printing quality. What I am trying to do is to automate the process of going into Gimp and adjusting the DPI values. Since Imagemagick is known to be superb and I used it for many other tasks I tried to achieve my goal with this tool. But it does just not do what I want. After trying a lot of things I think this actually is be the command that should be my friend: convert input.png -density 300 output.png This should set the DPI to 300, as I can read everywhere in the web. It seems to work. When I check the file it stays the same. file input.png output.png input.png: PNG image data, 611 x 453, 8-bit grayscale, non-interlaced output.png: PNG image data, 611 x 453, 8-bit grayscale, non-interlaced When I use this command, it seems like it did what I wanted: identify -verbose output.png | grep 300 Resolution: 300x300 PNG:pHYs : x_res=300, y_res=300, units=0 (Funny enough, the same output comes for input.png which confuses me... so this might be the wrong parameters to watch?) But when I now render my TeX with "pdflatex" the image is still big and blurry. Also when I open the image with Gimp again the DPI values are set to "72" instead of "300". So there actually was no effect at all. Now what is the problem here. Am I getting something completely wrong? I can't be that wrong since everything works just fine with Gimp... Thanks for any help in this. I am also open to other automated solutions which are easily done on a Linux system...

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  • Windows 7 .NET 3.5.1 - 2.0 Slightly Corrupted, How to Repair?

    - by Quinxy von Besiex
    My Windows 7 included .NET installation (3.5 to 2.0) appears very slightly and particularly corrupted and I am trying to fix it without reinstalling Windows or trying to revert to backups. Everything was working and then my hard drive started corrupting a few files and checkdisk found bad clusters so I imaged the drive to a new one. As soon as I booted on the new drive everything worked except programs which call the System.Net.NetworkInformation methods within .NET 3.5 to 2.0 (like Ping() and IsNetworkAvailable()), which immediately crash the app in which the calls are (those calls in .NET 4.0 works fine). Those methods are found inside System.dll, and I assume call native methods which I believe are inside winnsi.dll or iphlpapi.dll or something else (I've not found this yet); I assume it calls native methods because the exception which causes the crash is Fatal Execution Engine Error which people mention is usually related to calling native methods and marshaling data between them. A huge clue about the culprit is likely found in the fact that when I launch the exact same crashing application through a code profiler (which executes the exe and captures stats on which methods took the longest) the app works fine, no crash at all! How could running it within the profiler work and running it outside not work? That seems the key to the mystery. I've used procmon to catch all the registry, filesystem, and network events from the crashing execution and the profiler-run successful execution and compared the two outputs but didn't learn much (I see the moment at which the non-profiled app crashes, but up until then they behave the same, loaded the same modules, ). The only big difference seems to be that at the moment before the app crash the profiler-executed code creates 4-6 new threads and the directly executed code only creates 1-2. I have diffed the files/directories which seemed most relevant (the .NET stuff under Windows and Program Files) pre- and post- disk trouble and seen no changes where I didn't expect any (no obvious file corruption). I have diffed the software and system registry hives pre- and post- disk trouble and seen no changes which seemed relevant. I have created a new user account and cleaned up any environment variables in case environment was related. No change. I did "sfc /scannow" and it found no integrity problems. I tried "ngen update" to regenerate pre-compiled code in case I missed something that might be damaged and nothing changed. I assume I need to repair my .NET installation but because Windows 7 included .NET 3.5 - 2.0 you can't just re-run a .NET installer to redo it. I do not have access to the Windows disks to try to re-install Windows over itself (the computer has a recovery partition but it is unusable); also the drive uses a whole-disk encryption solution and re-installing would be difficult. I absolutely do not want to start from scratch here and install a fresh Windows, reinstall dozens of software packages, try and remember dozens of development-related customizations/etc. Given all that... does anyone have any helpful advice? I need .NET 3.5 - 2.0 working as I am a developer and need to build and test against it. Thanks! Quinxy

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  • Varnish POST problem "9 FetchError c backend write error: 11" for application/x-www-form-urlencoded content

    - by ompap
    Cutting a longish story short, we have managed to get a more precise error out of Varnishlog. Varnishlog tells us that we are sending a 31 TxRequest - POST 31 TxHeader - Content-Type: application/x-www-form-urlencoded but we are getting 9 FetchError c backend write error: 11 31 BackendClose - [backend name] 9 VCL_call c error 9 VCL_return c deliver 9 Length c 488 9 VCL_call c deliver 9 VCL_return c deliver 9 TxProtocol c HTTP/1.1 9 TxStatus c 503 We still do not know what this is exactly, but apparently Content-Type: application/x-www-form-urlencoded is not getting through as it should. Help still needed, please! Original message below. The title was "Varnish not letting Joomla users to log in - 503 guru meditation error", but I changed it to get more attention to the problem and not to the symptoms. Hello, We have a production site for a local newspaper which is currently behind an Apache reverse proxy, basicly the site on one server and the other being reserved as a reverse proxy only (well, there is more but that has no relevance here). Apache as a reverse proxy works, but could be faster. We want to change the reverse proxy to use Varnish instead of Apache on an Ubuntu 10.4 Server. The Varnish is version 2.10 installed directly from Ubuntu repos. Ubuntu 10.4 uses PHP 5.3.2. For anonymous surfers the site works wonderfully with Varnish. So far we can get very good speed out of Varnish, we just have a few problems with logging in or out. The big one is, that the users cannot log in: they get a Varnish 503 error page every time. The logs do not reveal the cause. It feels as if the request would never leave Varnish. So we are merely guessing - not a strong starting point. We have gone through what has been suggested on various plces on the web. We have increased the timeouts to backend xxx { .host = "xxx.xx"; .port = "http"; .connect_timeout = 60s; .first_byte_timeout = 60s; .between_bytes_timeout = 60s; } but we seem to get the 503 guru error page much faster than that, as in approx. 5 seconds. We have increased the Varnish headers size to 128 in daemon. In vcl_recv we have if (req.http.Authenticate || req.http.Authorization) { return(pass); } and in vcl_fetch ## auhtentication handling if (req.http.Authenticate || req.http.Authorization) { return(pass); } We do not strip cookies. We have tried to make sure that error pages are not cached. As said above, we cannot see anything in the backend Apache logs, apparently it never gets asked for Joomla user authentication. Varnish does not seem to get much mentioning with connection to Joomla. (We cannot dump Joomla, that selection has been done and we just have to live with what we have been given) Has anyone a working Varnish - Joomla combination? Thanks for reading. Please help. We need some hints - desperately. Any suggestions? ompap

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  • Weird Network Behavior of Home Router

    - by Stilgar
    First of all I would like to apologize because what you are going to read will be long and confusing but I am fighting this issue for 3 days now and am out of ideas. At home I have the following setup 50Mbps Internet connects into a home router A 2 desktop computers connect to router A via standard FTP LAN cables including one where the cable is ~20m long. a second router B connects to router A via standard FTP LAN cable X (~20m long). several devices connect to the wireless network of router B and there are a couple of desktop computers connected to it through FTP LAN cables. For some reason computers connected to router B when it is connected via cable X have very slow Internet connection. It is like 5 times slower than what is expected. This is the actual problem I am trying to solve. Interesting facts If a computer is connected to cable X directly instead of through router B the Internet speed is just fine (up to the 50Mbps I get from the ISP). Tested with two computers. I have tried replacing router B with another router C and the problem persists. If I connect router B via another cable to the same ports with the same settings everything seems to work fine and computers connected to router B have quite fast Internet I have tested mainly via Speedtest.net but I have also achieved similar speeds when downloading a file The upload speed is quite higher than the download speed in all cases. Note that my ISP usually has higher upload speed (unless it manages to hit the 50Mbps cap) It seems like the speed when connecting through router B with cable X is reduced 4-5 times no matter what the original speed is. For example via router B I get 10Mbps speed to local servers where I get 50Mbps when connected on router A. If I use a distant server where the ISP is only able to provide 25Mbps I get 4-5Mbps on router B. WiFi is slower than LAN on both routers (which is normal) but the reduced speed is reduced proportionally for WiFi. In addition the upload speed is normally higher from the ISP and it is also reduced proportionally. I have tried two different network configurations. One where I have NAT behind NAT where router B connects to router A via the WAN port and has its own DHCP. Second where router B connects to router A via standard LAN port and has DHCP disabled. In this configuration router B serves as a switch and the Network Gateway for computers connected to router B is the internal IP address of router A. Both configurations work just fine but both manifest the reduced speed issue. pings seem to work just fine As far as I can tell none of the cables is crossed The RJ45 setup for cable X orange orange-white brown brow-white blue blue-white green green-white This is a big problem for me since cable X passes through walls and floors and is very hard to replace. I also may have gotten some of the facts wrong because I am almost going crazy with this issue and testing includes going several floors up and down the staircase. One hypothesis I came up with is that the cable is defective in such a way that the voltage from the router affects its performance. When it is connected to a computer it performs just fine but the router has less power. Related hypothesis includes the cable being affected by electricity cables in the walls when the voltage is low. (I know nothing about electricity) So any ideas what to do, what to test or what the issue may be?

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  • Cannot read status the monit daemon, even with allowed group

    - by jefflunt
    I cannot seem to get monit status or other CLI commands to work. I've built monit v5.8 to run on a Raspberry Pi. I'm able to add services to be monitored, and the web interface can be accessed just fine, as I've set it up for public read-only access (it's a test server, not my final production setup, so not a big deal right now). Problem is, when I run monit status while logged in as root I get: # monit status monit: cannot read status from the monit daemon I also have monit started on boot via this /etc/inittab file entry: mo:2345:respawn:/usr/local/bin/monit -Ic /etc/monitrc I've verified that monit is running, and I'm getting email alerts anytime I either kill the monit process manually, or reboot my raspberry pi. So, next I check my monitrc file permissions to see which group is allowed access. # ls -al /etc/monitrc -rw------- 1 root root 2359 Aug 24 14:48 /etc/monitrc Here's my relevant allow section of the control file. set httpd port 80 allow [omitted] readonly allow @root allow localhost allow 0.0.0.0/0.0.0.0 Also tried setting permissions on this file to 640 to allow group read permissions, but no matter what I try I either get the same error as noted above, or when the permissions are set to 640 I get: # monit status monit: The control file '/etc/monitrc' must have permissions no more than -rwx------ (0700); right now permissions are -rw-r----- (0640). What am I missing here? I know that the httpd must be enabled, as that's the interface that the CLI uses to get information (or so I've read), so I've done that. And in terms of monit doing its monitoring job and sending email alerts, that's all working as well. Here's my entire monitrc file - again, this is version v5.8, and it was build with both PAM and SSL support. The process runs under the root user: # Global settings set daemon 300 with start delay 5 set logfile /var/log/monit.log set pidfile /var/run/monit.pid set idfile /var/run/.monit.id set statefile /var/run/.monit.state # Mail alerts ## Set the list of mail servers for alert delivery. Multiple servers may be ## specified using a comma separator. If the first mail server fails, Monit # will use the second mail server in the list and so on. By default Monit uses # port 25 - it is possible to override this with the PORT option. # set mailserver smtp.gmail.com port 587 username [omitted] password [omitted] using tlsv1 ## Send status and events to M/Monit (for more informations about M/Monit ## see http://mmonit.com/). By default Monit registers credentials with ## M/Monit so M/Monit can smoothly communicate back to Monit and you don't ## have to register Monit credentials manually in M/Monit. It is possible to ## disable credential registration using the commented out option below. ## Though, if safety is a concern we recommend instead using https when ## communicating with M/Monit and send credentials encrypted. # # set mmonit http://monit:[email protected]:8080/collector # # and register without credentials # Don't register credentials # # ## Monit by default uses the following format for alerts if the the mail-format ## statement is missing:: set mail-format { from: [email protected] subject: $SERVICE $DESCRIPTION message: $EVENT Service: $SERVICE Date: $DATE Action: $ACTION Host: $HOST Description: $DESCRIPTION Monit instance provided by chicagomeshnet.com } # Web status page set httpd port 80 allow [omitted] readonly allow @root allow localhost allow 0.0.0.0/0.0.0.0 ## You can set alert recipients whom will receive alerts if/when a ## service defined in this file has errors. Alerts may be restricted on ## events by using a filter as in the second example below.

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  • Cisco ASA not forwarding traffic from one interface to another

    - by Antoine Benkemoun
    Hello ServerFault, I am needing help in the configuration process of my Cisco ASA 5510. I have set up 4 Cisco ASA interconnected together via a big LAN. Each Cisco ASA has 3 or 4 LANs attached to them. The IP routing part is taken care of by OSPF. My problem is on another level. A computer connected to one of the LANs attached to an ASA has no problem communicating with the outside world. The outside world being anything "after" the ASA. My problem is that I am completely unable to have them communicate with another LAN connected to the same ASA. To rephrase this, I am unable to send traffic from one interface of a given ASA to another interface of the same ASA. My configuration is the following : ! hostname Fuji ! interface Ethernet0/0 speed 100 duplex full nameif outside security-level 0 ip address 10.0.0.2 255.255.255.0 no shutdown ! interface Ethernet0/1 speed 100 duplex full nameif cs4 no shutdown security-level 100 ip address 10.1.4.1 255.255.255.0 ! interface Ethernet0/2 speed 100 duplex full no shutdown ! interface Ethernet0/2.15 vlan 15 nameif cs5 security-level 100 ip address 10.1.5.1 255.255.255.0 ! interface Ethernet0/2.16 vlan 16 nameif cs6 security-level 100 ip address 10.1.6.1 255.255.255.0 ! interface Management0/0 speed 100 duplex full nameif management security-level 100 ip address 10.6.0.252 255.255.255.0 ! access-list nat_cs4 extended permit ip 10.1.4.0 255.255.255.0 any access-list acl_cs4 extended permit ip 10.1.4.0 255.255.255.0 any access-list nat_cs5 extended permit ip 10.1.5.0 255.255.255.0 any access-list acl_cs5 extended permit ip 10.1.5.0 255.255.255.0 any access-list nat_cs6 extended permit ip 10.1.6.0 255.255.255.0 any access-list acl_cs6 extended permit ip 10.1.6.0 255.255.255.0 any ! access-list nat_outside extended permit ip any any access-list acl_outside extended permit ip any 10.1.4.0 255.255.255.0 access-list acl_outside extended permit ip any 10.1.5.0 255.255.255.0 access-list acl_outside extended permit ip any 10.1.6.0 255.255.255.0 ! nat (outside) 0 access-list nat_outside nat (cs4) 0 access-list nat_cs4 nat (cs5) 0 access-list nat_cs5 nat (cs6) 0 access-list nat_cs6 ! static (outside,cs4) 0.0.0.0 0.0.0.0 netmask 0.0.0.0 static (outside,cs5) 0.0.0.0 0.0.0.0 netmask 0.0.0.0 static (outside,cs6) 0.0.0.0 0.0.0.0 netmask 0.0.0.0 ! static (cs4,outside) 10.1.4.0 10.1.4.0 netmask 255.255.255.0 static (cs4,cs5) 10.1.4.0 10.1.4.0 netmask 255.255.255.0 static (cs4,cs6) 10.1.4.0 10.1.4.0 netmask 255.255.255.0 ! static (cs5,outside) 10.1.5.0 10.1.5.0 netmask 255.255.255.0 static (cs5,cs4) 10.1.5.0 10.1.5.0 netmask 255.255.255.0 static (cs5,cs6) 10.1.5.0 10.1.5.0 netmask 255.255.255.0 ! static (cs6,outside) 10.1.6.0 10.1.6.0 netmask 255.255.255.0 static (cs6,cs4) 10.1.6.0 10.1.6.0 netmask 255.255.255.0 static (cs6,cs5) 10.1.6.0 10.1.6.0 netmask 255.255.255.0 ! access-group acl_outside in interface outside access-group acl_cs4 in interface cs4 access-group acl_cs5 in interface cs5 access-group acl_cs6 in interface cs6 ! router ospf 1 network 10.0.0.0 255.255.255.0 area 1 network 10.1.4.0 255.255.255.0 area 1 network 10.1.5.0 255.255.255.0 area 1 network 10.1.6.0 255.255.255.0 area 1 log-adj-changes ! There is nothing really complicated in this configuration. It just NATs from one interface to another and that's it. I have tried enabling same-security-traffic permit inter-interface but that doesn't help. I therefore must be missing something a little bit more complicated. Does anyone know why I cannot foward traffic from one interface to another ? Thank you in advance for your help, Antoine

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  • I cut-to-move DCIM folder to ext SD when an auto android OS update popped up b4 I could choose target - Cannot recover 200+ photos

    - by ZeroG
    I was downloading my Exhibit II's DCIM camera folder (with month's of photos inside) to its external SD card, in order to transfer them into my laptop. In my overconfidence, I hurriedly chose cut-to-move (rather than copy-to-move) when KABOOM! —an automatic Android OS update popped up before I could choose the target!!! I figured everything was in cache & calmly tried to go through with the update. But that was not a typically seamless event. It showed downloading icon but hmm… since I rooted the phone it brought the command line up & recovery sequence. But neither Android nor I had yet downloaded any alternate custom ROM Files to internal SD to update from! So were they trying to make me unroot my phone by giving me some bogus update on the fly or just give me a hard time in trying to hand me down an unrooted ROM that I'd have to figure out how to root again? Yes, I know there was that blurb about overwriting a file of the same name but I was trying to shake the darn stubborn update being forced on my phone during this precarious moment. I thought I had frozen or turned off all those auto-updates previously. Anyway, phones are small & fingers are big (sigh)... I tried to reboot into safe mode but the resultant photo file was partially overwritten (200 files had names but Zero bytes in them). I thought maybe it was still hung in cache or deposited somewhere else but I have searched everywhere with file managers. Since I did not have Titanium backing up camera, photo folder or gallery, I cannot recover 200+ photos. Dumb. You can understand my dilemma as I am involved in the arts & although just a camera phone, most of these photos were historic & aesthetic or at least as to subject matter. Photo-ops don't reoccur. I have tried a couple of recovery apps from the market like Search Duplicates & Recover to no avail. I was only able to salvage stuff I'd sent out in messages. I've got several decades in computers & this is such a miserable beginner's piece of bad luck I can't believe it happened to me. They were precious photos! Yes, I turned on Titanium since & yes I even tried USB to laptop recoveries. Being on a MacBookPro I'm trying androidfiletransfer.dmg, but I'd have to upgrade to Peach Sunrise to get above Android 3.0 for that App to recognize the phone via USB & the programmer says installation zeros your data, so that pretty much toasts any secret hidden places where these photos may have been deposited. Don't want to do that & am still trying to find them. They certainly didn't make it to my external SD Card. If any of you techies out there know anything, please help & thanks. Despite decades of being in computing, unfamiliar & ever-changing hard or software can humble even the most seasoned veterans.

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  • What was scientifically shown to support productivity when organizing/accessing file and folders?

    - by Tom Wijsman
    I have gathered terabytes of data but it has became a habit to store files and folders to the same folder, that folder could be kind of seen as a Inbox where most files (non-installations) enter my system. This way I end up with a big collections of files that are hard to organize properly, I mostly end up making folders that match their file type but then I still have several gigabytes of data per folder which doesn't make it efficient such that I can productively use the folder. I'd rather do a few clicks than having to search through the files, whether that's by some software product or by looking through the folder. Often the file names themselves are not proper so it would be easier to recognize them if there were few in a folder, rather than thousands of them. Scaling in the structure of directory trees in a computer cluster summarizes this problem as following: The processes of storing and retrieving information are rapidly gaining importance in science as well as society as a whole [1, 2, 3, 4]. A considerable effort is being undertaken, firstly to characterize and describe how publicly available information, for example in the world wide web, is actually organized, and secondly, to design efficient methods to access this information. [1] R. M. Shiffrin and K. B¨orner, Proc. Natl. Acad. Sci. USA 101, 5183 (2004). [2] S. Lawrence, C.L. Giles, Nature 400, 107–109 (1999). [3] R.F.I. Cancho and R.V. Sol, Proc. R. Soc. London, Ser. B 268, 2261 (2001). [4] M. Sigman and G. A. Cecchi, Proc. Natl. Acad. Sci. USA 99, 1742 (2002). It goes further on explaining how the data is usually organized by taking general looks at it, but by looking at the abstract and conclusion it doesn't come with a conclusion or approach which results in a productive organization of a directory hierarchy. So, in essence, this is a problem for which I haven't found a solution yet; and I would love to see a scientific solution to this problem. Upon searching further, I don't seem to find anything useful or free papers that approach this problem so it might be that I'm looking in the wrong place. I've also noted that there are different ways to term this problem, which leads out to different results of papers. Perhaps a paper is out there, but I'm not just using the same terms as that paper uses? They often use more scientific terms. I've once heard a story about an advocate with a laptop which has simply outperformed an advocate with had tons of papers, which shows how proper organization leads to productivity; but that story didn't share details on how the advocate used the laptop or how he had organized his data. But in any case, it was way more useful than how most of us organize our data these days... Advice me how I should organize my data, I'm not looking for suggestions here. I would love to see statistics or scientific measurement approaches that help me confirm that it does help me reach my goal.

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  • Linux not buffering block I/O when the device is not "in use" (i.e. mounted)

    - by Radek Hladík
    I am installing new server and I've found an interesting issue. The server is running Fedora 19 (3.11.7-200.fc19.x86_64 kernel) and is supposed to host a few KVM/Qemu virtual servers (mail server, file server, etc..). The HW is Intel(R) Xeon(R) CPU 5160 @ 3.00GHz with 16GB RAM. One of the most important features will be Samba server and we have decided to make it as virtual machine with almost direct access to the disks. So the real HDD is cached on SSD (via bcache) then raided with md and the final device is exported into the virtual machine via virtio. The virtual machine is again Fedora 19 with the same kernel. One important topic to find out is whether the virtualization layer will not introduce high overload into disk I/Os. So far I've been able to get up to 180MB/s in VM and up to 220MB/s on real HW (on the SSD disk). I am still not sure why the overhead is so big but it is more than the network can handle so I do not care so much. The interesting thing is that I've found that the disk reads are not buffered in the VM unless I create and mount FS on the disk or I use the disks somehow. Simply put: Lets do dd to read disk for the first time (the /dev/vdd is an old Raptor disk 70MB/s is its real speed): [root@localhost ~]# dd if=/dev/vdd of=/dev/null bs=256k count=10000 ; cat /proc/meminfo | grep Buffers 2621440000 bytes (2.6 GB) copied, 36.8038 s, 71.2 MB/s Buffers: 14444 kB Rereading the data shows that they are cached somewhere but not in buffers of the VM. Also the speed increased to "only" 500MB/s. The VM has 4GB of RAM (more that the test file) [root@localhost ~]# dd if=/dev/vdd of=/dev/null bs=256k count=10000 ; cat /proc/meminfo | grep Buffers 2621440000 bytes (2.6 GB) copied, 5.16016 s, 508 MB/s Buffers: 14444 kB [root@localhost ~]# dd if=/dev/vdd of=/dev/null bs=256k count=10000 ; cat /proc/meminfo | grep Buffers 2621440000 bytes (2.6 GB) copied, 5.05727 s, 518 MB/s Buffers: 14444 kB Now lets mount the FS on /dev/vdd and try the dd again: [root@localhost ~]# mount /dev/vdd /mnt/tmp [root@localhost ~]# dd if=/dev/vdd of=/dev/null bs=256k count=10000 ; cat /proc/meminfo | grep Buffers 2621440000 bytes (2.6 GB) copied, 4.68578 s, 559 MB/s Buffers: 2574592 kB [root@localhost ~]# dd if=/dev/vdd of=/dev/null bs=256k count=10000 ; cat /proc/meminfo | grep Buffers 2621440000 bytes (2.6 GB) copied, 1.50504 s, 1.7 GB/s Buffers: 2574592 kB While the first read was the same, all 2.6GB got buffered and the next read was at 1.7GB/s. And when I unmount the device: [root@localhost ~]# umount /mnt/tmp [root@localhost ~]# cat /proc/meminfo | grep Buffers Buffers: 14452 kB [root@localhost ~]# dd if=/dev/vdd of=/dev/null bs=256k count=10000 ; cat /proc/meminfo | grep Buffers 2621440000 bytes (2.6 GB) copied, 5.10499 s, 514 MB/s Buffers: 14468 kB The bcache was disabled while testing and the results are same on faster (newer) HDDs and on SSD (except for the initial read speed of course). To sum it up. When I read from the device via dd first time, it gets read from the disk. Next time I reread it gets cached in the host but not in the guest (thats actually the same issue, more on that later). When I mount the filesystem but try to read the device directly it gets cached in VM (via buffers). As soon as I stop "using" it, buffers are discarded and the device is not cached anymore in the VM. When I looked into buffers value on the host I realized that the situation is the same. The block I/O gets buffered only when the disk is in use, in this case it means "exported to a VM". On host, after all the measurement done: 3165552 buffers On the host, after the VM shutdown: 119176 buffers I know it is not important as the disks will be mounted all the time but I am curious and I would like to know why it is working like this.

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  • Performance Tuning a High-Load Apache Server

    - by futureal
    I am looking to understand some server performance problems I am seeing with a (for us) heavily loaded web server. The environment is as follows: Debian Lenny (all stable packages + patched to security updates) Apache 2.2.9 PHP 5.2.6 Amazon EC2 large instance The behavior we're seeing is that the web typically feels responsive, but with a slight delay to begin handling a request -- sometimes a fraction of a second, sometimes 2-3 seconds in our peak usage times. The actual load on the server is being reported as very high -- often 10.xx or 20.xx as reported by top. Further, running other things on the server during these times (even vi) is very slow, so the load is definitely up there. Oddly enough Apache remains very responsive, other than that initial delay. We have Apache configured as follows, using prefork: StartServers 5 MinSpareServers 5 MaxSpareServers 10 MaxClients 150 MaxRequestsPerChild 0 And KeepAlive as: KeepAlive On MaxKeepAliveRequests 100 KeepAliveTimeout 5 Looking at the server-status page, even at these times of heavy load we are rarely hitting the client cap, usually serving between 80-100 requests and many of those in the keepalive state. That tells me to rule out the initial request slowness as "waiting for a handler" but I may be wrong. Amazon's CloudWatch monitoring tells me that even when our OS is reporting a load of 15, our instance CPU utilization is between 75-80%. Example output from top: top - 15:47:06 up 31 days, 1:38, 8 users, load average: 11.46, 7.10, 6.56 Tasks: 221 total, 28 running, 193 sleeping, 0 stopped, 0 zombie Cpu(s): 66.9%us, 22.1%sy, 0.0%ni, 2.6%id, 3.1%wa, 0.0%hi, 0.7%si, 4.5%st Mem: 7871900k total, 7850624k used, 21276k free, 68728k buffers Swap: 0k total, 0k used, 0k free, 3750664k cached The majority of the processes look like: 24720 www-data 15 0 202m 26m 4412 S 9 0.3 0:02.97 apache2 24530 www-data 15 0 212m 35m 4544 S 7 0.5 0:03.05 apache2 24846 www-data 15 0 209m 33m 4420 S 7 0.4 0:01.03 apache2 24083 www-data 15 0 211m 35m 4484 S 7 0.5 0:07.14 apache2 24615 www-data 15 0 212m 35m 4404 S 7 0.5 0:02.89 apache2 Example output from vmstat at the same time as the above: procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 8 0 0 215084 68908 3774864 0 0 154 228 5 7 32 12 42 9 6 21 0 198948 68936 3775740 0 0 676 2363 4022 1047 56 16 9 15 23 0 0 169460 68936 3776356 0 0 432 1372 3762 835 76 21 0 0 23 1 0 140412 68936 3776648 0 0 280 0 3157 827 70 25 0 0 20 1 0 115892 68936 3776792 0 0 188 8 2802 532 68 24 0 0 6 1 0 133368 68936 3777780 0 0 752 71 3501 878 67 29 0 1 0 1 0 146656 68944 3778064 0 0 308 2052 3312 850 38 17 19 24 2 0 0 202104 68952 3778140 0 0 28 90 2617 700 44 13 33 5 9 0 0 188960 68956 3778200 0 0 8 0 2226 475 59 17 6 2 3 0 0 166364 68956 3778252 0 0 0 21 2288 386 65 19 1 0 And finally, output from Apache's server-status: Server uptime: 31 days 2 hours 18 minutes 31 seconds Total accesses: 60102946 - Total Traffic: 974.5 GB CPU Usage: u209.62 s75.19 cu0 cs0 - .0106% CPU load 22.4 requests/sec - 380.3 kB/second - 17.0 kB/request 107 requests currently being processed, 6 idle workers C.KKKW..KWWKKWKW.KKKCKK..KKK.KKKK.KK._WK.K.K.KKKKK.K.R.KK..C.C.K K.C.K..WK_K..KKW_CK.WK..W.KKKWKCKCKW.W_KKKKK.KKWKKKW._KKK.CKK... KK_KWKKKWKCKCWKK.KKKCK.......................................... ................................................................ From my limited experience I draw the following conclusions/questions: We may be allowing far too many KeepAlive requests I do see some time spent waiting for IO in the vmstat although not consistently and not a lot (I think?) so I am not sure this is a big concern or not, I am less experienced with vmstat Also in vmstat, I see in some iterations a number of processes waiting to be served, which is what I am attributing the initial page load delay on our web server to, possibly erroneously We serve a mixture of static content (75% or higher) and script content, and the script content is often fairly processor intensive, so finding the right balance between the two is important; long term we want to move statics elsewhere to optimize both servers but our software is not ready for that today I am happy to provide additional information if anybody has any ideas, the other note is that this is a high-availability production installation so I am wary of making tweak after tweak, and is why I haven't played with things like the KeepAlive value myself yet.

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  • VirtualBox - Public Static IP for a Debian Guest on a Dedicated Server

    - by user86296
    Goal: I want to run a Debian-squeeze-Guest in VirtualBox and it's own public static ip. I found tons of threads about this topic, but all in all I'm now trying for 10 hours (reading the manual, the forums, trying to learn about networking concepts & commands) to give a Guest his own public static ip (so that the Guest is similar to a vServer you can order from a hosting company), but wasn't able to. Since I'm a big noob as far as networking stuff is concerned, I'm probably doing something wrong.(please bear with me :-) ) Situation: VirtualBox 4.0.10 (headless no gui) is running on a dedicated Debian-Server, the Guest OS is Debian as well. The server has a static ip and I ordered an additional ip for a VM. Problem description: Upto now I was able to use NAT to access the VM from the outside and to setup an internal network between several Guests and all of this worked very well. When setting NIC 1 to bridged and configuring a public static ip on the guest, the guest was unpingable. (neither from outside, nor from the host) I could connect to the guest via the internal network, from another vm, though. ( VBoxManage controlvm VMGuest nic1 bridged eth0 ) ( configuration attempt of static-ip on the guest '/etc/network/interfaces' is below) Please let me know what I'm doing wrong, or what I can try to get it to work, or if you need more info. I think I've read that with a current VirtualBox-version for bridged networking no special host-configuration is necessary, is that accurate, or might that be the problem? Additional Info Info I got from the hosting company about the additional IP Please note that you can use the IP address only for this server. IP: 46.4.xx.xx Gateway: 46.4.xx.xx Mask: 255.255.255.248 VBoxManage showvminfo VMGuest |less ... NIC 1: MAC: 080027D72F7B, Attachment: Bridged Interface 'eth0', Cable connected: on, Trace: off (file: none), Type: 82540EM, Reported speed: 0 Mbps, Boot priority: 0 NIC 2: MAC: 080027B03B75, Attachment: Internal Network 'InternalNet1', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0 NIC 3: disabled (...rest is disabled) cat /etc/network/interfaces on the Host-machine # Loopback device: auto lo iface lo inet loopback # device: eth0 auto eth0 iface eth0 inet static address 46.4.xx.xx broadcast 46.4.xx.xx netmask 255.255.255.224 gateway 46.4.xx.xx post-up mii-tool -F 100baseTx-FD eth0 # default route to access subnet up route add -net 46.4.xx.xx netmask 255.255.255.224 gw 46.4.xx.xx eth0 cat /etc/network/interfaces on the Guest-VM # This file describes the network interfaces available on your system # and how to activate them. For more information, see interfaces(5). # The loopback network interface auto lo iface lo inet loopback # The primary network interface allow-hotplug eth0 auto eth0 iface eth0 inet static address 46.4.xx.xx netmask 255.255.255.248 gateway 46.4.xx.xx auto eth1 iface eth1 inet dhcp ifconfig -a on the Guest shows the correct static ip for eth0 but the Guest is unreachable "over eth0" eth0 Link encap:Ethernet HWaddr 08:00:27:d7:2f:7b inet addr:46.4.xx.xx Bcast:46.4.xx.xx Mask:255.255.255.248 inet6 addr: fe80::a00:27ff:fed7:2f7b/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:21 errors:0 dropped:0 overruns:0 frame:0 TX packets:69 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1260 (1.2 KiB) TX bytes:3114 (3.0 KiB) eth1 Link encap:Ethernet HWaddr 08:00:27:b0:3b:75 inet addr:192.168.10.3 Bcast:192.168.10.255 Mask:255.255.255.0 inet6 addr: fe80::a00:27ff:feb0:3b75/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:142 errors:0 dropped:0 overruns:0 frame:0 TX packets:92 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:15962 (15.5 KiB) TX bytes:14540 (14.1 KiB) Interrupt:16 Base address:0xd240 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:123 errors:0 dropped:0 overruns:0 frame:0 TX packets:123 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:25156 (24.5 KiB) TX bytes:25156 (24.5 KiB)

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  • How to understand these lines in apache.log

    - by chefnelone
    I just get 19000 lines like these in the apache.log file for my site example.com. My hosting provider shut down the hosting and notified me that I need to avoid to activate my hosting again. I understand that I got a big amount of visits but I don't know how to avoid this. 88.190.47.233 - - [27/Jun/2013:09:51:34 +0200] "GET / HTTP/1.0" 403 389 "http://example.com/" "Opera/9.80 (Windows NT 6.1; U; ru) Presto/2.10.289 Version/12.02" 417 88.190.47.233 - - [27/Jun/2013:09:51:34 +0200] "GET / HTTP/1.0" 403 389 "http://example.com/" "Opera/9.80 (Windows NT 6.1; U; ru) Presto/2.10.289 Version/12.02" 417 175.44.28.155 - - [27/Jun/2013:09:51:44 +0200] "GET /en/user/register HTTP/1.1" 403 503 "http://example.com/en/" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1;)" 248 175.44.29.140 - - [27/Jun/2013:09:53:19 +0200] "GET /en/node/1557?page=2 HTTP/1.0" 403 517 "http://example.com/en/node/1557?page=2" "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.12 Safari/535.11" 491 These are the lines from apache-error.log. There are more than 35000 lines like this. [Thu Jun 27 09:50:58 2013] [error] [client 5.39.19.183] (13)Permission denied: access to /index.php denied, referer: http://example.com/ [Thu Jun 27 09:51:03 2013] [error] [client 125.112.29.105] (13)Permission denied: access to /index.php denied, referer: http://example.com/en/ [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.php denied, referer: http://example.com/en/node/1557?page=1#comment-701 [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.php denied, referer: http://example.com/en/node/1557?page=1#comment-701 [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.html denied, referer: http://example.com/en/node/1557?page=1#comment-701 [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.htm denied, referer: http://example.com/en/node/1557?page=1#comment-701 [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.php denied, referer: http://example.com/ [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.html denied, referer: http://example.com/ [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.htm denied, referer: http://example.com/ [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.php denied, referer: http://example.com/ [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.html denied, referer: http://example.com/ [Thu Jun 27 09:51:34 2013] [error] [client 88.190.47.233] (13)Permission denied: access to /index.htm denied, referer: http://example.com/ [Thu Jun 27 09:51:44 2013] [error] [client 175.44.28.155] (13)Permission denied: access to /index.php denied, referer: http://example.com/en/ [Thu Jun 27 09:53:19 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.php denied, referer: http://example.com/en/node/1557?page=2 [Thu Jun 27 09:53:20 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.php denied, referer: http://example.com/en/node/1557?page=2 [Thu Jun 27 09:53:20 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.html denied, referer: http://example.com/en/node/1557?page=2 [Thu Jun 27 09:53:20 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.htm denied, referer: http://example.com/en/node/1557?page=2 [Thu Jun 27 09:53:21 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.php denied, referer: http://example.com/ [Thu Jun 27 09:53:21 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.html denied, referer: http://example.com/ [Thu Jun 27 09:53:21 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.htm denied, referer: http://example.com/ [Thu Jun 27 09:53:22 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.php denied, referer: http://example.com/ [Thu Jun 27 09:53:22 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.html denied, referer: http://example.com/ [Thu Jun 27 09:53:22 2013] [error] [client 175.44.29.140] (13)Permission denied: access to /index.htm denied, referer: http://example.com/ [Thu Jun 27 09:56:53 2013] [error] [client 113.246.6.147] (13)Permission denied: access to /index.php denied, referer: http://example.com/en/ [Thu Jun 27 09:58:58 2013] [error] [client 108.62.71.180] (13)Permission denied: access to /index.php denied, referer: http://example.com/

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  • Performing mechanical movements using computer

    - by Vi
    How to make a computer (in particular, my laptop) to perform some mechanical movements without buying anything $5, soldering things inside computer or creating big sophisticated circuits? Traditionally CD-ROM tray is used to make computer do some movement IRL by, for example, SSH command, but in laptop tray is one-shot (unless manually reloaded) and also not very comfortable [mis]usage. Some assistance circuits can be in use too, but not complex. For example, there is a little motor that can work on USB power. Devices in my computer: DVD-ROM tray: one-time push. USB power: continuous power to the motor or LEDS or relay that turns on something powerful. Audio card. 3 outputs (modprobe alsa model=test can set Mic and Line-in as additional output). One controllable DC output (microphone) that can power up LED and some electronic (may be even mechanic?) relay. Also with sophisticated additional circuiting can control a lot of devices with a good precision. Both input and output support. Probably the most useful object in computer for radio ham. Modem. Don't know about this much, it doesn't work because of hsfmodem crashes kernel if memory is = 1GB. May be it's "pick up" and "hang up" can turn on and off power taken from USB port? Video card. VGA port? S-Video port? Will them be useful? Backlight. Tunable, but probably unuseful. CardBus (or some) slot. Nothing interesting for the task probably (is it?). AC adapter and battery. Probably nothing programmable here. /* My AC adapter already have additional jacks to connect extra devics */ Keyboard. No use. Touchpad. Good sensor (synclient -m 1), but no output. Various LEDs inside laptop. Probably too weak and requires soldering. Fans inside laptop. Poor control over them, requires soldering and dangerous to tinker. HDD (internal and external) that can be spin down and up (hdparm -Y, cat /dev/ubb). But connecting anything serially with it's power line makes HDD underpowered... And too complex. Is something are missed? Any ideas how to use described components? Any other ideas? May be there are easily available /* in developing countries */ cheap devices like "enhanced multimeters" that are controllable from computer and can provide configurable output and measure current and other things? Things to aid pushing many physical buttons with computer. Isn't this a simple idea and implementation and a lot of use in good hands?

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  • Why do we need different CPU architecture for server & mini/mainframe & mixed-core?

    - by claws
    Hello, I was just wondering what other CPU architectures are available other than INTEL & AMD. So, found List of CPU architectures on Wikipedia. It categorizes notable CPU architectures into following categories. Embedded CPU architectures Microcomputer CPU architectures Workstation/Server CPU architectures Mini/Mainframe CPU architectures Mixed core CPU architectures I was analyzing the purposes and have few doubts. I taking Microcomputer CPU (PC) architecture as reference and comparing others. Embedded CPU architecture: They are a completely new world. Embedded systems are small & do very specific task mostly real time & low power consuming so we do not need so many & such wide registers available in a microcomputer CPU (typical PC). In other words we do need a new small & tiny architecture. Hence new architecture & new instruction RISC. The above point also clarifies why do we need a separate operating system (RTOS). Workstation/Server CPU architectures I don't know what is a workstation. Someone clarify regarding the workstation. As of the server. It is dedicated to run a specific software (server software like httpd, mysql etc.). Even if other processes run we need to give server process priority therefore there is a need for new scheduling scheme and thus we need operating system different than general purpose one. If you have any more points for the need of server OS please mention. But I don't get why do we need a new CPU Architecture. Why cant Microcomputer CPU architecture do the job. Can someone please clarify? Mini/Mainframe CPU architectures Again I don't know what are these & what miniframes or mainframes used for? I just know they are very big and occupy complete floor. But I never read about some real world problems they are trying to solve. If any one working on one of these. Share your knowledge. Can some one clarify its purpose & why is it that microcomputer CPU archicture not suitable for it? Is there a new kind of operating system for this too? Why? Mixed core CPU architectures Never heard of these. If possible please keep your answer in this format: XYZ CPU architectures Purpose of XYZ Need for a new architecture. why can't current microcomputer CPU architecture work? They go upto 3GHZ & have upto 8 cores. Need for a new Operating System Why do we need a new kind of operating system for this kind of archictures?

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  • IBM Server Config questions

    - by Joel Coel
    I have a few questions on a potential server setup. First, the situation: Last year we bought an IBM x3500 server with 2 Xeon E5410's, 9GB RAM, 6 HDDs. The original intent for this server was to replace the old exchange e-mail server. It was brought in, set up, and then shortly after we switched to gmail. Shortly after that my predecessor left for greener pastures, and finally I was hired. So this nice server is now sitting (mostly) idle. This year I have budget again for one server, and of course I want to put this other server to work. I'm thinking about the best use for the two server, and I think I finally have a plan for what I want to do with them. The idea is to use the two newer servers as a pair of VM hosts. I will set up each server with the same 8 VMs, but divide up the load so that only 4 are active per physical host. That means I've normally got 2GB RAM + 2 cores per host. I've done some load testing to pick out what servers to convert to virtual, and chose them so that each host will be capable of handling the entire set of 8 by itself in a pinch with 1 core and 1GB RAM, but would be very taxed to do so. This should take our data center from 13 total servers down to 7. The "servers" I'm replacing are mostly re-purposed desktops, so I'm more than happy to be able to do this. Now it's time to go shopping for the new server. I'd like my two hosts to match as closely as possible, and so I'm looking at IBM again. It also helps that we have some educational matching grant money from IBM that I need to use to help pay for this system (we're a small private college). So finally, (if you're not bored already), we come to my questions: Am I missing anything big or obvious in this plan? I'm a little worried about network performance since the VM hosts will only have 4 nics total where 8 used to be, but I don't think it will be a problem. Is there anything else like this I might be overlooking? Am I making it even too complicated? IBM no longer has a good analog to last year's server. If I want to match the performance (8 cores, 9GB RAM, 1333mhz front side bus, 6 spindles), I have to spend quite a bit more than we paid last year: $2K+, or nearly a 33% cost increase. This only brings a marginal increase in performance. The alternative to stay in budget is to take a hit on the fsb down to 800mhz or cut the number of cores in half, neither of which is attractive. The main cost culprit is the processor. IBM no longer offers the E5410. It's listed as a part, but not available in any of the server configs I've looked at. I'm considering getting the cheapest 800mhz fsb dual core xeon I can configure and then buying the E5410's separately. That's still an extra $350 I wasn't counting on, but that's better than $2K. I want to know what others think of this - will it work or will I end up with the wrong motherboard or some other issue? Am I missing a simple way to configure the server I really want? I don't really intend to do this, but one option to save some money back is to omit the redundant power supply. Since my redundancy plan for these system is to switch over to a completely different host, the extra power isn't fully necessary. That said, it's still very helpful to avoid even short downtimes while I switch over VMs. Has anyone done this?

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  • Does this prove a network bandwidth bottleneck?

    - by Yuji Tomita
    I've incorrectly assumed that my internal AB testing means my server can handle 1k concurrency @3k hits per second. My theory at at the moment is that the network is the bottleneck. The server can't send enough data fast enough. External testing from blitz.io at 1k concurrency shows my hits/s capping off at 180, with pages taking longer and longer to respond as the server is only able to return 180 per second. I've served a blank file from nginx and benched it: it scales 1:1 with concurrency. Now to rule out IO / memcached bottlenecks (nginx normally pulls from memcached), I serve up a static version of the cached page from the filesystem. The results are very similar to my original test; I'm capped at around 180 RPS. Splitting the HTML page in half gives me double the RPS, so it's definitely limited by the size of the page. If I internally ApacheBench from the local server, I get consistent results of around 4k RPS on both the Full Page and the Half Page, at high transfer rates. Transfer rate: 62586.14 [Kbytes/sec] received If I AB from an external server, I get around 180RPS - same as the blitz.io results. How do I know it's not intentional throttling? If I benchmark from multiple external servers, all results become poor which leads me to believe the problem is in MY servers outbound traffic, not a download speed issue with my benchmarking servers / blitz.io. So I'm back to my conclusion that my server can't send data fast enough. Am I right? Are there other ways to interpret this data? Is the solution/optimization to set up multiple servers + load balancing that can each serve 180 hits per second? I'm quite new to server optimization, so I'd appreciate any confirmation interpreting this data. Outbound traffic Here's more information about the outbound bandwidth: The network graph shows a maximum output of 16 Mb/s: 16 megabits per second. Doesn't sound like much at all. Due to a suggestion about throttling, I looked into this and found that linode has a 50mbps cap (which I'm not even close to hitting, apparently). I had it raised to 100mbps. Since linode caps my traffic, and I'm not even hitting it, does this mean that my server should indeed be capable of outputting up to 100mbps but is limited by some other internal bottleneck? I just don't understand how networks at this large of a scale work; can they literally send data as fast as they can read from the HDD? Is the network pipe that big? In conclusion 1: Based on the above, I'm thinking I can definitely raise my 180RPS by adding an nginx load balancer on top of a multi nginx server setup at exactly 180RPS per server behind the LB. 2: If linode has a 50/100mbit limit that I'm not hitting at all, there must be something I can do to hit that limit with my single server setup. If I can read / transmit data fast enough locally, and linode even bothers to have a 50mbit/100mbit cap, there must be an internal bottleneck that's not allowing me to hit those caps that I'm not sure how to detect. Correct? I realize the question is huge and vague now, but I'm not sure how to condense it. Any input is appreciated on any conclusion I've made.

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  • Performance issues when using SSD for a developer notebook (WAMP/LAMP stack)?

    - by András Szepesházi
    I'm a web application developer using my notebook as a standalone development environment (WAMP stack). I just switched from a Core2-duo Vista 32 bit notebook with 2Gb RAM and SATA HDD, to an i5-2520M Win7 64 bit with 4Gb RAM and 128 GB SDD (Corsair P3 128). My initial experience was what I expected, fast boot, quick load of all the applications (Eclipse takes now 5 seconds as opposed to 30s on my old notebook), overall great experience. Then I started to build up my development stack, both as LAMP (using VirtualBox with a debian guest) and WAMP (windows native apache + mysql + php). I wanted to compare those two. This still all worked great out, then I started to pull in my projects to these stacks. And here came the nasty surprise, one of those projects produced a lot worse response times than on my old notebook (that was true for both the VirtualBox and WAMP stack). Apache, php and mysql configurations were practically identical in all environments. I started to do a lot of benchmarking and profiling, and here is what I've found: All general benchmarks (Performance Test 7.0, HDTune Pro, wPrime2 and some more) gave a big advantage to the new notebook. Nothing surprising here. Disc specific tests showed that read/write operations peaked around 380M/160M for the SSD, and all the different sized block operations also performed very well. Started apache performance benchmarking with Apache Benchmark for a small static html file (10 concurrent threads, 500 iterations). Old notebook: min 47ms, median 111ms, max 156ms New WAMP stack: min 71ms, median 135ms, max 296ms New LAMP stack (in VirtualBox): min 6ms, median 46ms, max 175ms Right here I don't get why the native WAMP stack performed so bad, but at least the LAMP environment brought the expected speed. Apache performance measurement for non-cached php content. The php runs a loop of 1000 and generates sha1(uniqid()) inisde. Again, 10 concurrent threads, 500 iterations were used for the benchmark. Old notebook: min 0ms, median 39ms, max 218ms New WAMP stack: min 20ms, median 61ms, max 186ms New LAMP stack (in VirtualBox): min 124ms, median 704ms, max 2463ms What the hell? The new LAMP performed miserably, and even the new native WAMP was outperformed by the old notebook. php + mysql test. The test consists of connecting to a database and reading a single record form a table using INNER JOIN on 3 more (indexed) tables, repeated 100 times within a loop. Databases were identical. 10 concurrent threads, 100 iterations were used for the benchmark. Old notebook: min 1201ms, median 1734ms, max 3728ms New WAMP stack: min 367ms, median 675ms, max 1893ms New LAMP stack (in VirtualBox): min 1410ms, median 3659ms, max 5045ms And the same test with concurrency set to 1 (instead of 10): Old notebook: min 1201ms, median 1261ms, max 1357ms New WAMP stack: min 399ms, median 483ms, max 539ms New LAMP stack (in VirtualBox): min 285ms, median 348ms, max 444ms Strictly for my purposes, as I'm using a self contained development environment (= low concurrency) I could be satisfied with the second test's result. Though I have no idea why the VirtualBox environment performed so bad with higher concurrency. Finally I performed a test of including many php files. The application that I mentioned at the beginning, the one that was performing so bad, has a heavy bootstrap, loads hundreds of small library and configuration files while initializing. So this test does nothing else just includes about 100 files. Concurrency set to 1, 100 iterations: Old notebook: min 140ms, median 168ms, max 406ms New WAMP stack: min 434ms, median 488ms, max 604ms New LAMP stack (in VirtualBox): min 413ms, median 1040ms, max 1921ms Even if I consider that VirtualBox reached those files via shared folders, and that slows things down a bit, I still don't see how could the old notebook outperform so heavily both new configurations. And I think this is the real root of the slow performance, as the application uses even more includes, and the whole bootstrap will occur several times within a page request (for each ajax call, for example). To sum it up, here I am with a brand new high-performance notebook that loads the same page in 20 seconds, that my old notebook can do in 5-7 seconds. Needless to say, I'm not a very happy person right now. Why do you think I experience these poor performance values? What are my options to remedy this situation?

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