/ - rtt - IT Resource

  • syntax error, unexpected T_SL in PHP Solution


    This happened in a PHP script with heredoc but it could really happen anywhere.  The issue was whitespace in code like this:   $variable = <<< HTML   some stuff here   $othervar HTML;   Notice on the first line that there is extra white space after the HTML.  Whitespace was a deadly killer since it isn't obvious in terms of syntax.........
  • MySQL Using mytop Debug Source of High IO and Slow Performance


    mytop is one of my favorite tools and it is fairly simple aside from a few caveats and issues that persist to this day. To install it on Centos: yum -y install centos Configure ~/.mytop vi ~/.mytop user=root host=localhost db=test #port=3306 socket=/var/lib/mysql/mysql.sock header=1 color=1 Try runni........
  • Firefox An error occurred during a connection to some-ip-or-domain. SSL peer reports incorrect Message Authentication Code. Error code: SSL_ERROR_BAD_MAC_ALERT Solution


    An error occurred during a connection to some-ip-or-domain. SSL peer reports incorrect Message Authentication Code. Error code: SSL_ERROR_BAD_MAC_ALERT     The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.     Please contact the website owners to inform them of this problem. **Solution** Go to about:config........
  • VPN Account Buyers Guide and General Info


    What does VPN stand for? VPN stands for Virtual Private Network and is a secure way of connecting networks and devices. In the context we're talking about it will usually be a client-server solution and not connecting whole networks or businesses. The assumption is that most people reading this are trying to secure their internet connection, privacy and hide or change their IP address. Why use a VPN? There are many........
  • How to install grub on virtio KVM with Linux


    I messed up the bootloader by accident on a standard Centos 6.3 install because I turned the /dev/vda1 boot partition into an mdadm raid 1.  This was all done correctly aside from one point I didn't realize was an issue metadata=00.90 is the only thing that will allow you to boot (otherwise grub won't work and you won't boot). So the next step is rescue mode from a CD right? The problem you will find is that grub does not detect your hard drives, this is I believe is be........
  • Dell Perci 6/i Firmware Upgrade Guide Tutorial


      One thing to remember is that you need MegaCli to do the flashing. You also need the correct file, I tried at least 2 different Perc 6 firmwares from Dell that kept getting rejected as corrupt by MegaCli (they were really the wrong version).  I have an external PCI-E Dell 6 Perc/I but I chose images from the 'Integrated" on motherboard version as it was all I could find.  They are different, and below is my first time finding success.........
  • Dell Perc 6/i cannot downgrade


    I flashed an LSI Logic firmware to it and it broke the BIOS (cannot do Ctrl+R) for booting purposes but allows other functionality to work normally. I tried downgrading to a Dell firmware for Perc 6i but it won't work, not even with MegaCli wget http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN --2013-08-26 12:53:39--  http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN Resolvi........
  • "Cannot load certificate file keys/server.crt: error:0906D06C:PEM" OpenVPN Solution


    Cannot load certificate file keys/server.crt: error:0906D06C:PEM The .crt is blank empty because when generating it I kept hitting enter for the defaults and this caused the crt not to be signed. Certificate is to be certified until Dec 18 00:35:49 2022 GMT (3650 days) Sign the certificate? [y/n]:y 1 out of 1 certificate requests certified, commit? [y/n]y So if you get messages like these, a........
  • The Importance of a High Quality Power Supply/Power Supplies To Prevent Overheating/System Crash/Hardware Damage


    For years I've always built cheap systems believing that there is little difference in more expensive components when it comes to reliability and quality, I generally believe this still except for Power Supplies. I've always bought cheap cases with nice sounding 350-550W stock/cheap/crap power supplies and haven't had any issues for the most part until recently. One such case is an NGEAR case with a 550W Optimax power supply, I always read that these supplies don't produce the........
  • convert carat ^M/M Windows based text files to Linux


    carat M isn't this symbol ^ that you think, it can only be produced by typing "Ctrl-v, Ctrl-m". That you might see in text files saved from Windows. tofrodos is the package that has dos2unix which is basically the same scripts that replace ^M with /n tofrodos is the Debian/Buntu package name which has the dos2unix and unix2dos binaries........
  • Openvz YUM Error Solution to "[Errno -1] Metadata file does not match checksum Trying other mirror."


    It's weird because I have a nearly identical box and setup and I can update the ovzkernel-PAE* just fine but on this box it doesn't work. I only get this error with the openvz.repo and not others such as Centos-Base.repo With my other server it works normally: ================ Setting up Update Process Resolving Dependencies --> Running transaction check ---> Package ovzkernel-PAE.i686 0:2.6.18-238.12.1.el5.0........
  • encrypt bash scripts to hide source code


    http://www.datsi.fi.upm.es/~frosal/ SHC is a program written by the author above that does just that, it's a great little tool to have. Some have said it isn't exactly encrypting the code but just making it hard to read by obfuscating the code. There was also a good discussion about that here:........
  • Understanding /etc/aliases from sendmail when using with postfix or other MTA's


    understanding /etc/aliases *remember to apply changes you need to run "newaliases" after editing /etc/aliases one thing I don't get is that it doesn't allow you to specify the whole e-mail address on the left-hand side eg: yourfullemail@domain.com: someotheremail@domain.com postalias: warning: /etc/aliases, line 109: name must be local (if you try the above) It works more like this: your........
  • Installing Webmin & Enabling SSL


    Webmin Setup Centos 5: wget http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html&ts=1294339690&use_mirror=surfnet [1] 24229 [2] 24230 [root@host ~]# --2011-01-06 21:48:20--  http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html Resolving downloads.sourceforge.net... 216.34.181.........
  • mdadm RAID 1 adventures


    I separated the 2 drives in the RAID 1 array. 1 is the old one /dev/sda and is out of date, while the separated other one /dev/sdc was in another drive and mounted and used with more data (updated). I wonder how mdadm will handle this: usb-storage: device scan complete md: md127 stopped. md: bind<sda3> md: md127: raid array is not clean -- starting background reconstruction raid1: raid set md127 active with 1 out of 2 m........
  • Wine stopped working/won't work Solution


    After an upgrade wine wouldn't open anything, not even the pre-installed notepad. There are no wine logs and nothing is mentioned in any standard log file about why. I finally decided to run wine from the shell and see what's going on: wine client error:0: version mismatch 398/402. Your wineserver binary was not upgraded correctly, or you have an older one somewhere in your PATH. Or maybe the wrong wineserver is still running?........
  • SolusVM/Xen Central Backup Warning - Takes System Off-line!


    This really gives me a bad impression of SolusVM. I tried the "Central Backup" option and it does not warn that your server gets shutdown instantly in order to do the backup! Further, there is no way to pause or cancel the backup.  Thankfully this is a test/small disk usage VPS but what if someone was running something production with a large filesize? I haven't used QuickBackup but hope that isn't the same thing. Everyone should be vary car........
  • Ubuntu 10.04 Linux is still not ready for the Desktop world


    I am a huge fan of Linux and the idea of OpenSource but I've said it many times, there are still hurdles in today in 2010 for Linux as a Desktop.  Linux is still intended for servers at its very core.  This can be changed succesfully though, as Apple has shown us with Mac OS X based on FreeBSD. Half of the issue is lack of driver support and the other half is the Linux Kernel and Window Manages, KDE and GNome still both don't cut it (but they're getting closer). I'll........
  • mencoder Linux CLI video editing how to encode video file into xvid and split by time into multiple parts


    Mencoder is great, you can throw anything at it, including video files from your camera and have it encode into xvid or almost any other format. In my case I took 640x480 video from my Canon and reduced the size by 1/3 with the options below (there are many other options that you can read about in the manual but I like to keep it simple).  Mencoder Encode mencoder <filename.avi> -ovc xvid -oac mp3lame -xvidencopts fixed_quant=4 -o <output.avi>........
  • Intel Corei5 750 Complaint/Onboard Video Issue on Intel H57 chipset not working


    Do you have an LGA1156 board and wonder why your onboard video isn't working?  It's probably because there is no GPU integrated on the board itself, it is supposed to be on the CPU and new CPU's from Intel don't come with it! I was shocked to learn that you can buy a motherboard with onboard video which doesn't work.  I never knew it was being done or possible, but to make it worse the latest Core i5's don't have video on the die of the CPU. This means having on........
  • Picking an FTPD (vsftpd) Server in Linux Centos/Debian


    I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find. yum search ftp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile  * rpmforge: ftp-stud.fht-esslingen.de  * base: mirrors.netdna.com  * updates: updates.interworx.info  * addons: yum.singlehop.com  * extras: mirrors.netdna.com rpmforge   ........
  • Clustered/Distributed Network Filesystems, Which Ones live up to the hype?


    I've tried to find a good sensible solution to cluster with and each technology has it's pros and cons and there is no perfect solution and I've found a lot of "exaggerations" in the applications, benefits and performance of these different filesystems. DRBD I first started off with DRBD and I have to say it does live up to the hype, is quite reliable (although it can be annoying to match up the kernel module and user applications since they must match and whe........
  • MySQL Restoring And Dumping/Backing UP MySQL Data/Tables/Databases


    Backing MySQL Databases Backing Up/Dumping All Mysql Databases To A Single File mysqldump --all-databases -u admin -p > allmysqldatabases.sql The "-all-databases" clause is pretty obvious isn't it?  It means that it will backup all databases. The "-u admin" means login using the user "admin", if you h........
  • Apple iPhone 3GS and predecessors are leading a revolution


    As much of a computer nerd as I am, I'm usually a late adopter to technology for a few reasons.  I feel most new hyped technologies and electronics are mainly fads, and I'm also cheap. Adopting later means you avoid the bugs, kinks and most importantly pay the lowest price, that's me being cheap again :) I never read much about the iPhone but I saw all the hype around it and until recently I wasn't a big fan of anything Apple until a few years ago I realize........
  • RTL8111/8168B R8169 Gigabit Link slow speeds


    This is the Intel Atom 330 motherboard with integrated Realtek Gigabit NIC (Intel Desktop Board D945GCLF2 Motherboard W/ Atom 330 1.6 GHz Dual Core Processor - Mini-ITX) I cannot achieve more than 15 MB/s, even doing a local transfer through eth0 to it's own IP. 100%   95MB  15.9MB/s   00:06 So this is not a cabling, switch or hardware issue, it seems like a driver or chipset limitation problem. Here is my........
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