/ - rtt - IT Resource

  • systemd management using systemctl and journalctl to check systemd logs


    systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system. The key commands or arguments you will use with systemctl are the following: Unit Commands:   list-units [PATTERN...]         List loaded units &nbs........
  • AMD Set Fan Speed and Other Powerplay Memory/CPU Timings with a Linux script


    You can do other things but this particular script is just to set all AMD cards to 80% fan speed (remember this script needs to applied everytime you reboot). You could set it is a cron or just throw it into /etc/rc.local basepath=/sys/class/drm for hwmon in `ls -1 /sys/class/drm|grep card[0-99]$`; do echo card=$hwmon; hwmonname=`ls $basepath/$hwmon/device/hwmon|grep hwmon[0-99]` hwmonpath=$basepath/$hwmon/device/hwmon/$hwmonname echo "ec........
  • How To Enable Nested KVM so guests can virtualize with hardware extensions


    #check if nested KVM is enabled by doing a cat on nested inside sys root@s14:~# cat /sys/module/kvm_intel/parameters/nested  root@s14:~# echo "options kvm-intel nested=Y" > /etc/modprobe.d/kvm-intel.conf root@s14:~# echo "options kvm-amd nested=1" > /etc/modprobe.d/kvm-amd.conf root@s14:~# modprobe -r kvm_intel modprobe: FATAL: Module kvm_intel is in use. root@s14:~# modprob........
  • OVF Tool: Error: Task failed on server: This host does not support Intel VT-x. VMWare VCenter install On ESXi ERror


    Intel VT-X is enabled in Virtualbox but it doesn't seem to pass through the needed vmx extension despite the following variables on the host confirming it is enabled: cat /sys/module/kvm_intel/parameters/nested Y cat /sys/module/kvm_intel/parameters/ept Y     OVF Tool: Disk progress: 99% OVF Tool: Transfer Completed OVF Tool: Powering on VM: Embedded-vCenter-Server-Appliance- OVF Tool: Task p........
  • VMWare 6.7 VCSA VSphere ESXi Management SSO Install Guide on Linux using the CLI


    #mount the VCSA DVD mount /dev/sr0 /mnt/cd #alternatively you could mount the iso directly mount -o loop vcsa.iso /your/mount/path #for this purpose we are using the CLI installer on Linux cd /mnt/cd/vcsa-cli-installer/lin64 #no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file ./vcsa-deploy Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
  • Linux Mint Black Screen after boot no graphics solution


    This is not the normal "black screen" issue and I was shocked to eventually find out why.  The normal advice of reconfiguring Xorg didn't work.  Even booting into "Recovery Mode" did not help. Here is the short end of the stick that fixed it: sudo apt-get install mdm mate-desktop-environment Yes you got it right, mdm and the mate-desktop-environment / gnome were somehow uninstalled.  This must be whe........
  • [Wed Sep 20 15:34:44 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Wed Sep 20 15:34:44 2017] [error] Init: Unable to read server certificate from file /www/ssl-certs/server.crt [Wed Sep 20 15:34:44 2017] [error] SSL Library Err


    [Wed Sep 20 15:34:44 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Wed Sep 20 15:34:44 2017] [error] Init: Unable to read server certificate from file /www/ssl-certs/server.crt [Wed Sep 20 15:34:44 2017] [error] SSL Library Error: 218529960 error:0D0680A8:asn1 encoding routines:ASN1_CHECK_TLEN:wrong tag [Wed Sep 20 15:34:44 2017] [error] SSL Library Error: 218595386 error:0D07803A:asn1 encoding routines:ASN1_ITEM_EX_D2I:nested asn1 error........
  • Centos 5.9 Working Vault Repo file


    Centos 5 is not supported running yum will produce an error like this: YumRepo Error: All mirror URLs are not using ftp, http[s] or file.  Eg. Invalid release/ removing mirrorlist with no valid mirrors: /var/cache/yum/base/mirrorlist.txt Error: Cannot find a valid baseurl for repo: base Solution - Update this file CentOS-Base.repo   # CentOS-Base.repo........
  • ffmpeg Linux Mint download, compile and install howto


    #if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used wget http://ffmpeg.org/releases/ffmpeg-3.3.2.tar.bz2 tar -jxvf ffmpeg-3.3.2.tar.bz2 cd  ffmpeg-3.3.2/ ./configure --disable-yasm install prefix            /usr/local source path              ........
  • Centos 7 A start job is running for dev-mapper-clx2droot.device (8min 44s / no limit)


    This error is usually because of some sort of encryption in this case a Seagate enclosure with encryption (even though not enabled) did not allow this hard drive to boot.........
  • Linux SAMBA does not work with symlinks


    At first I thought it's just not possible but there is actually an option that can be enabled to make symlinks work with Samba. Then I put this under the [global] section Note: It's "wide links" and not "wide symlinks" (some other sites have incorrect info which was a frustrating waste of time :))   Add this to your smb.conf follow symlinks = yes wide links = yes unix ex........
  • Centos 5 OpenSSL does not support TLS 1.2 Apache Error


    [Thu Jan 26 14:13:31 2017] [notice] caught SIGTERM, shutting down [Thu Jan 26 14:14:00 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Thu Jan 26 14:14:00 2017] [error] Server certificate is expired: 'Server-Cert' [Thu Jan 26 14:14:00 2017] [notice] SSL FIPS mode disabled [Thu Jan 26 14:14:07 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Thu Jan 26 14:14:07 2017] [error] Server certificate is expired: 'Server-Ce........
  • cPanel Install Error kernel ipv6 module support solution


    2017-01-12 14:25:36  529 (ERROR): The installer was unable to verify that your kernel supports IPv6. 2017-01-12 14:25:36  530 (ERROR): The message received when trying to create an IPv6 socket was Address already in use 2017-01-12 14:25:36  531 (ERROR): Please ensure that the ipv6 module is enabled and loaded in your kernel. 2017-01-12 14:25:36  532 (FATAL): Exiting... Solution This happened........
  • ADATA SU800 256GB 3D NAND Flash SSD Test & Review


    I keep reading these drives are slower, but they are cheap and still SSD and work very fast for my needs. As you can see the sequential read is 481-491MB/s, if I put them in MDADM RAID10 mode (normal RAID1) they should give me well over 900MB/s and with redundancy and being very cheap for what they offer. [1232206.315622] scsi 8:0:1:0: Direct-Access     ATA      ADATA SU800   &........
  • mcp55 NIC not working at boot on Centos 6.6-6.8


    forcedeth 0000:00:08.0: irq 25 for MSI/MSI-X forcedeth 0000:00:08.0: eth0: MSI enabled forcedeth 0000:00:08.0: eth0: no link during initialization ADDRCONF(NETDEV_UP): eth0: link is not ready forcedeth 0000:00:08.0: eth0: link up ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready Dec  1 18:21:32 box15 kernel: forcedeth: Reverse Engineered nForce ethernet driver. Version 0.64. Dec  1 18:21:32 box15 kernel........
  • Linux Mint 17 How to Enable File Sharing Option in File Manager


    I still cannot understand how this would not be enabled by default and I struggled to find the reason why with manually installing samba etc.. wondering why the option for sharing was not in the menu.   On Linux Mint "MATE" the package is called "caja-share" and on Cinnamon it is called "nemo-share" so edit the below command as necessary: *Also note that the "samba" package is necessary as it is not inst........
  • iptables: Applying firewall rules: iptables-restore: line 40 failed


     service iptables start  iptables: Applying firewall rules: iptables-restore: line 40 failed                                                            [FAILED]........
  • MySQL PHP adding a backslash/escaping apostrophes Solution


    The first thing to diagnose is what is actually in the database (use PHPMyAdmin or CLI). You will of course either find that the backslash is either in the database or not. If the backslash is in the database you probably have magic quotes gpc/runtime on and/or are calling the "addslashes()" function which does this. If you are escaping your data with mysql_real_escape_string() then think again, you probably have magic quotes gpc enabled either in php.ini or........
  • How To Record Your Screen with Linux


    Istanbul: At least in Linux Mint the latest 17.2 version Istanbul freezes when "In process of saving to Disk" even with the workaround of not having Sound recording enabled.  It looks like a great app but bugs like this seem to have plague it for over 8 years! Kazam: This little app works great, its only bug is that when you try to tell it to record a window or area it puts a gray cov........
  • Installing zoneminder on Ubuntu/Debian Linux Howto


    sudo apt-get install zoneminder [sudo] password for one: Reading package lists... Done Building dependency tree       Reading state information... Done The following packages were automatically installed and are no longer required:   libuser-perl python-evince kdebase-apps kwrite unixodbc   libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp   python-mediaprof........
  • OpenVZ Install Guide Again / Quick Setup


    yum -y install wget wget -P /etc/yum.repos.d/ http://ftp.openvz.org/openvz.repo rpm --import http://ftp.openvz.org/RPM-GPG-Key-OpenVZ yum -y install vzkernel vzctl #enable ip_forward sed -i s/'net.ipv4.ip_forward = 0'/'net.ipv4.ip_forward = 1'/g /etc/sysctl.conf #all interfaces should not send redirects echo "net.ipv4.conf.default.send_redirects = 1" >> /etc/sysctl.conf echo "net.ipv4.co........
  • HP Procurve Switch 2824 CLI Telnet Experience , Guide and Tutorial


    telnet 192.168.1.54 ------------------------------------- ProCurve J4903A Switch 2824 Software revision I.10.77 Copyright (C) 1991-2009 Hewlett-Packard Co.  All Rights Reserved.                            RESTRICTED RIGHTS LEGEND  Use, duplication, or disclosure by the Government is subject........
  • Vbox/Virtualbox devices grayed out for non-root user solution


    <p>It is a permissions issue that is hard to fix.</p> <p><strong>All but one USB device is greyed out.</strong></p> <p>I am already a member of &quot;vboxusers&quot;</p> <ul> <li>I have already enabled and disabled USB support for the guest.</li> <li>I have already reinstalled the latest VBOx guest editions</li> <li>If running as root it all works fine</li> <li>Changing........
  • How to root and unlock S4 in Canada Bell/Rogers/Telus/Fido I337 4.4.2


    <p>i337 Canada on Bell is hard to root or even install TWRP<br /> <br /> Installed TWRP from Odin and my computer gave me the bluescreen at the end but it seemed to be successful (after ODIN said reset).<br /> TWRP mode does not seem to enter, instead you get the Android recovery mode with Volume up + Home<br /> <br /> <br /> http://galaxys4root.com/galaxy-s4-root/how-to-root-att-or-verizon-galaxy-s4-on-android-4-4-2/<br /> <br /> 1.)........
  • Openvz iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. solution


    iptables -t nat -A PREROUTING -p tcp -m tcp -d 192.168.2.1/32 --dport 3389 -j DNAT --to-destination 192.168.5.2:3389 iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. The above is often because you don't have the correct modules loaded on the hostnode or enabled for the container but in some cases it's actually a weird openvz setting. Che........
  • Asterisk VOIP Sipura/Linksys PAP2T Calls Not Being Received Solution


    This problem seemed to happen recently but was likely causing issues before where the phone(s) do not ring. Now there are a few reasons why this can happen especially if your adapter has DND mode enabled (disable it). However that wasn't my issue and I only figured it out the other day  when  by fluke if you're on the phone (making a call) then  calls will come in. That's when I figured out the solution: This likely app........
  • What a hdd hard drive and mdadm RAID array failure looks like in Linux


    [3805108.257042] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257052] sd 0:0:0:0: [sda] Write Protect is off [3805108.257054] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00 [3805108.257066] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [3805108.257083] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257090] sd 0:0:0:0: [sda] Write Protect is off........
  • Asterisk iptables block bruteforce attacks howto with fail2ban


    yum -y install fail2ban vi /etc/fail2ban/jail.conf [asterisk-tcp] enabled  = true filter   = asterisk action   = iptables-multiport[name=asterisk-tcp, port="5060,5061", protocol=tcp]            sendmail-whois[name=Asterisk, dest=you@example.com, sender=fail2ban@example.com] logpath  = /var/log/asterisk/messages maxret........
  • Dell CS24-NV7 Howto Enable LAN/NICs and PXEBoot in the BIOS


    Dell CS24-NV7 Unusually the Virtualization was enabled when I got this server but all the NICs were diabled in the BIOS including PXE boot! Advanced -> Advanced Chipset Control PCI Slot 1 Option ROM: Enabled Onboard LAN1 Control: Enabled LAN1 Option ROM Scan: Enabled (you need it for PXE boot) Onboard LAN2 Control: Enabled LAN2 Option ROM Scan: Enabled *you will need to reboot and........
  • VBox/Virtualbox solution to NS_ERROR_CALL_FAILED error


    VBox/Virtualbox solution to NS_ERROR_CALL_FAILED error This is likely because you have 2D/3D acceleration enabled and your card doesn't support it. Eg. you switched video card drivers or video cards that did support it. The funny thing is that you CANNOT disable those options as they are "greyed" out in the VBox client GUI. The config file has to be manually changed and fixed with these options "accelerate3D="false" accelera........
  • kvm centos cannot compile error


    ./configure ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc yum -y install gcc make ./configure ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc yum -y install compat-gcc-* ./configure Error: Could not find alsa Make sure to have the alsa libs and headers installed. yum -y install alsa-lib-devel ./configure........
  • CPanel suhosin install failed


    /scripts/phpextensionmgr install PHPSuHosin Updating md5sum list Fetching http://httpupdate.cpanel.net/cpanelsync/easy/targz.yaml (connected:0).......(request attempt 1/12)...Resolving httpupdate.cpanel.net...(resolve attempt 1/65)...     Fetching http://httpupdate.cpanel.net/mirror_addr_list (connected:0).......(request attempt 1/3)......connecting to 74.50.120.123...@74.50.120.123......connected......receiving...100%......request success......Done........
  • htaccess block IPs while RewriteEngine/modrewrite is enabled solution


    I struggled with this for awhile because the normal setup won't work if modrewrite is being used: ORDER ALLOW, DENY   So the solution is something like this: <Limit GET HEAD POST> order allow,deny deny from 12.43.12.0/24 allow from all </LIMIT> ........
  • Dell FS12-NV7 2U Server Information and Guide


    I've got one of these for testing projects from work at home and got more than I bargained for with the time I've spent on it due to the storage handing/Perc 6/i cards. My particular model came with the following: 2U Rack Mount Server with Rails 2xOpteron 2373 EE (Quad Core, there is a 6-core version that can be found at times) 16GB RAM 2 x 250GB Seagate SATA 2 x Dell Perc 6/i (horrible and a nightmare to work........
  • LSI MegaRAID Adventures, Guide and HowTo


    LSi Megaraid At first it was configured as a RAID 0, then I deleted the Virtual Disk Group. I thought both drives would be shown and detected in Linux as sda and sdb but it actually shows nothing. To make them work you have to hit Ctrl+R before the system boots (when prompted) and create a Virtual Disk Group.  In my case I created each one as RAID 0 (with a single drive only) as I just wanted JBOD but there is no such option or default in these Dell Pe........
  • open /dev/kvm: No such file or directory failed to initialize KVM: Operation not permitted - Solution


    open /dev/kvm: No such file or directory failed to initialize KVM: Operation not permitted [   96.084502] kvm: disabled by bios Any of the above means that "Virtualization" is not enabled in your BIOS.  Most servers and Desktops (non-mainstream) can do this no problem but leave it off by default.  Note that some systems even though the CPU supports it, don't allow enabling of Virtualization for some reason (especially some lap........
  • WD 20EARX Dead Again


    Another new drive bad from the start:   Jun  2 15:14:18 one-desktop kernel: [15895.386779] ata2.00: exception Emask 0x50 SAct 0x1 SErr 0x280900 action 0x6 frozen Jun  2 15:14:18 one-desktop kernel: [15895.386782] ata2.00: irq_stat 0x08000000, interface fatal error Jun  2 15:14:18 one-desktop kernel: [15895.386784] ata2: SError: { UnrecovData HostInt 10B8B BadCRC } Jun  2 15:14:18 one-desktop kernel: [15895.386788] ata2.00: cmd 60/0........
  • Either the lower file is not in a valid eCryptfs format, or the key could not be retrieved. Plaintext passthrough mode is not enabled; returning -EIO


    I'm using ecryptfs and was suddenly unable to access or even ls my home directory (but every subfolder is accessible).  It just hangs and throws this message in messages/dmesg: Either the lower file is not in a valid eCryptfs format, or the key could not be retrieved. Plaintext passthrough mode is not enabled; returning -EIO I read somewhere that perhaps some file or folder is owned by root somehow, sure enough there are some and sudoing to root allows me to........
  • WD 20EARX 2TB Bad within days


    This is just trying to read 5GB off the drive with dd and the drive initially tested ok but shortly after I wondered why I was seeing 2MB/s read speeds.  Notice the "current_pending_sector", anytime I've seen it at anything above 0 even with no other bad fields/attributes, it means the drive is bad. ata1.00: exception Emask 0x0 SAct 0x3 SErr 0x0 action 0x0 ata1.00: irq_stat 0x40000008 ata1.00: failed command: READ FPDMA QUEUED ata1.00: cmd 60/00:00:........
  • sysctl how to apply values from /etc/sysctl.conf after changes


    If you make changes to /etc/sysctl.conf (which are permanent and not lost during reboot) but want them to apply with rebooting just use the following command: sysctl -p After that your changes will be enabled.........
  • Bad Hard Drive Slows Down Computer


    Here's a proven example of what a bad hard drive can do, it was technically functioning OK in a RAID array but the system became extremely low and the load become high and IOWAIT was even higher and I always thought it was a bad application.  The truth is that this failing 1TB Hitachi has slowly gotten worse and caused huge slowdowns, (eg. 100% load on Thunderbird waiting for e-mails to load etc..).  After swapping it out, tabs change instantly, emails are not lagged, and........
  • Hitachi Serial Numbers for Hard Drives without seeing the physical drive


    Here's what SMART tells me the serial number is: === START OF INFORMATION SECTION === Device Model:     Hitachi HDS721010CLA332 Serial Number:    JP2940HQ3ZY7KH Firmware Version: JP4OA3EA User Capacity:    1,000,204,886,016 bytes Device is:        Not in smartctl database [for details use: -P showall] ATA Version is:   8 ATA Standard is:&nb........
  • OpenVZ - how to manually restore a VPS from another host or backup


    There are 3 pieces that are required to restore and make it work (of course consider if any kernel modules need to re-enabled and if you need to change the IPs): Copy the vz/private/VEID directory to /vz/private Copy the /etc/vz/conf/VEID.conf to /etc/vz/conf/ mkdir /vz/root/VEID After that you should be able to see the VE in vzlist -a You should then be able to start it normally.........
  • Lantronix KVM/IP Keyboard/Mouse not working in BIOS before booting the OS


    I've run into two issues with Lantronix based KVMs on various servers and here's how I solved them (with that said I like these units as they are Java based and OS independent and work very well, unike some other models like Startech). 1.) If you are connected by USB only and you're sure USB support from the BIOS is enabled, you just need to click the following in Lantronix Interfaces -> Keyboard/Mouse Check "Force USB Full Speed Mode", this fixed the issu........
  • Disable SELinux How To Tutorial Solution


    Here is a quick script that works on most Centos versions to disable the virus/SELinux from blocking basic functionality. The first echo 0 statement disables SELinux instantly but it will still be enabled on reboot. The second line disables it permanently. #!/bin/bash #disable SELinux Immediately echo 0 > /selinux/enforce #disable SELinux Permanently sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config........
  • Centos 5 and OpenVZ won't boot after kernel install


    For whatever reason the current OpenVZ yum repo file enables the RHEL6 version of OpenVZ, why is this bad?  Because if you're running Centos 5 it still defaults to using the kernel from RHEL6 which won't work on RHEL5/Centos 5. I only realized this after wondering why I couldn't boot into OpenVZ that it was using one meant for RHEL6. To fix the problem you have to edit /etc/yum.repos.d/openvz.repo and disable the "[openvz-kernel-rhel6]" section by changing........
  • Linux/Centos how to block SSH bruteforce/dictionary attacks automatically with denyhosts


    A lot of people become nervous (and understandably so) when checking their auth or security logs, in Centos /var/log/secure and see dozens, hundreds of even thousands of attempted logins to various services, especially SSH. Of course you could manually block these people/IPs but no one has time to read the logs like that, what if some program or script could do it for you? This is what denyhosts does for you, it checks the logs and based on a certain number of failed SSH attem........
  • iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) - OpenVZ Container Problem iptables module problem solution


    iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) This solution applies to all other iptables modules/problems for OpenVZ, you'll just need to add them to both lists/lines below if you have modules other than what I have below. The modules need to be enabled in both iptables and the OpenVZ hostnode itself and then the containers which need it must be restarted. How To Enable IPTables Modules in OpenVZ........
  • Directadmin Enable SSL


    It's really silly how DA doesn't enable SSL by default but is otherwise a stable, fast and secure control panel. Here's a copy and paste way of enabling SSL for Directadmin in just a few seconds: *setup SSL openssl req -x509 -newkey rsa:1024 -keyout /usr/local/directadmin/conf/cakey.pem -out /usr/local/directadmin/conf/cacert.pem -days 9999 -nodes That creates the public certificate and private key pair in the location Directadmin expects to fi........
  • pcnet32: eth0: transmit timed out, status 97fb, resetting - NIC card problem solution


    I've encountered this problem before and I believe it  may affect other drivers (I could test but I don't have time).  This was happening on my custom Linux system with the pcnet32 driver. pcnet32: eth0: transmit timed out, status 97fb, resetting (and some other kernel module tracing in dmesg) Basically it means the card is connected (it shows connected in full duplex etc.. and recognized if the cable is disconnected too) but no packets can be sent or received........
  • vi disable color syntax highlighting/can't read syntax highlighting


    Within vi if you can't exit /etc/vim/vimrc you can type :syntax off And to turn it back on: :syntax on Many of us have a dark/black background in our terminal/shell making the default syntax unreadable, the solution is to either turn off syntax highlighting with :syntax off or to enable a special option in /etc/vim/vimrc Edit /etc/vim/vimrc The "syntax on" enables the highligh........
  • Linux Out of Memory OOM Object Killer Solution "Out of memory: kill process 1955 (sshd) score 81 or a child"


    I had a system running a 128MB live CD image with 2.8 gigs of available RAM and the OOM kernel killer went crazy when using dd for more than 8 minutes and kept killing everything.  I've read that this is due to a low-memory issue and paging in the kernel and 32-bit systems with lots of RAM. I even enabled swapspace on my LiveCD and the issue happened 25 minutes into dd rather than 8 minutes, so what gives? Also no swap space was ever used! cat /proc/s........
  • How To Test If Your Hard Drive Is Good/Signs of dying hard drive


    I like dd, although it only reads it, usually a read test of the entire disk will uncover if your hard drive is bad in some parts.  This is a good thing to do at least once a month, a lot of times bizarre program behavior, laginess and crashing/unnmounting problems etc.. are due to a failing disc and SMART won't know it or indicate a problem: We must also remember there's never a guarantee, I've found that ever since we moved to larger and more platters per drive with 1TB drives........
  • smart is not smart, it thinks a dead drive is still good


    I had a dying drive that smart thought until it totally disappeared was a good drive, and actually all parameters did look fine but this system was causing my system to lockup and other bad behavior:   === START OF INFORMATION SECTION === Device Model:     WDC WD20EARS-00MVWB0 Serial Number:    WD-WMAZ20139 Firmware Version: 50.0AB50 User Capacity:    2,000,398,934,016 bytes Device........
  • Hitachi 2TB HDS5C3020ALA632 drive DOA


    I had one of these shipped and it was not recognized when plugged in, here's what a dead drive looks like (I assume it's teh circuit board which is dead):   ata1: link is slow to respond, please be patient (ready=0) ata1: softreset failed (device not ready) ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) ata1: link online but device misclassified, retrying ata1: link is slow to respond, please be patient (ready=0) ata1: softreset f........
  • Kernel/make compilation time and how to improve compile times/compile the Linux kernel faster without hardware upgrades


    I thought only a faster CPU and SSD would help but I already have a Quad-Core CPU and it wasn't being maxed out.  The actual tests were performed on an AMD-V enabled 128MB dual core VMWare container though. There is a flag that can be passed to make in order to start multiple threads, by specifying 4 threads I was able to reduce the whole kernel compilation time from scratch by about 50%! (65minutes vs 31minutes!).  *Yes I did do a make clean before each co........
  • Linux High IOWAIT updatedb can't be killed and crash with mdadm


    high IO wait   424 root      39  19  1900  848  552 D  0.0  0.0   0:00.91 updatedb root       424  0.0  0.0   1900   848 ?        DN   Mar11   0:00 /usr/bin/updatedb -f sysfs?rootfs?bdev?proc?cpuset?binfmt_misc?debugfs?sockfs?usbfs?pipefs?anon_inodefs?futexfs?tmpfs?inotifyfs?eventp........
  • PHP5 & Apache Blank/White Screen/Page PHP won't work


    PHP5 & Apache Blank Screen/Page The PHP package is installed and works from the CLI Error reporting is enabled The only way I could get it working was: rm /etc/php.ini yum remove php yum install php-* -x php-pear* -x php-pecl* Interestingly enough reinstalling php did not bring back the deleted php.ini but everything is working.  ........
  • Failed to save enabled features : The Suexec command on your system is configured to only run scripts under /var/www, but the Virtualmin base directory is /home. CGI and PHP scripts run as domain owners will not be executed.


    Apache/httpd Failed to save enabled features : The Suexec command on your system is configured to only run scripts under /var/www, but the Virtualmin base directory is /home. CGI and PHP scripts run as domain owners will not be executed. This is because I never edited the Apache Config and Virtualmin config to reflect my new/current updated structure.........
  • Webmin/Virtualmin when enabling bind: Failed to save enabled features : Virtualmin is configured to setup DNS zones, but this system is not setup to use itself as a DNS server. Either add 127.0.0.1 to the list of DNS servers, or turn off the BIND fe


    Webmin/Virtualmin when enabling bind: Failed to save enabled features : Virtualmin is configured to setup DNS zones, but this system is not setup to use itself as a DNS server. Either add 127.0.0.1 to the list of DNS servers, or turn off the BIND feature on the module config page. It means what it says, add "127.0.0.1" to /etc/resolv.conf........
  • Virtualmin/Webmin Postfix Error: The status of your system is being checked to ensure that all enabled features are available, that the mail server is properly configured, and that quotas are active ..


    Virtualmin Postfix Error: The status of your system is being checked to ensure that all enabled features are available, that the mail server is properly configured, and that quotas are active ..       A problem was found with your Postfix virtual maps : No map sources were found in the Postfix configuration .. your system is not ready for use by Virtualmin. <- Solution  ........
  • Dying Seagate 7200.11 SD15


    [137392.910057] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x80000 action 0x6 frozen [137392.910077] ata4: SError: { 10B8B } [137392.910095] ata4.00: cmd 60/20:00:00:00:00/00:00:00:00:00/40 tag 0 ncq 16384 in [137392.910099]          res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout) [137392.910122] ata4.00: status: { DRDY } [137392.910135] ata4: hard resetting link [137393.440060] ata4: SATA link........
  • 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........
  • WD (Western Digital) Advanced Format Drive Lagged/Slow Speed/Performance/Design Flaw EAD/EARS problem WDC WD20EARS-00S8B1


    Let the numbers speak for themselves, from what I read the Load_Cycle_Count which is very high (more than 500,000/half a million times) is the number of head parks.  What a stupid "Green" design and design flaw which will probably mean an early life for the drive. This is almost as silly as Seagate's new reputation for BSY/poor quality disks since the 7200.11 series. To make it worse this is also when Western Digital introduced "Advanced Format" o........
  • Firefox plugin-container high CPU usage


    This is an easy fix and highlights a huge issue again with Linux and Flash still not playing nicely/working as well as Windows yet. Solution - Go to "about:config" and disable the two entries (set them to false):   dom.ipc.plugins.enabled.libflashplayer.so dom.ipc.plugins.enabled.libnptest.so........
  • http://apt.sw.be/redhat/el5/en/i386/test/repodata/repomd.xml: [Errno 14] HTTP Error 404: Not Found Trying other mirror.


    http://apt.sw.be/redhat/el5/en/i386/test/repodata/repomd.xml: [Errno 14] HTTP Error 404: Not Found Trying other mirror. Error: Cannot retrieve repository metadata (repomd.xml) for repository: rpmforge-testing. Please verify its path and try again Notice it is complaining about "rpmforge-testing", just disable it for now: Solution is to edit the repo: vi /etc/yum.repos.d/rpmforge-testing.repo........
  • 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>........
  • mdadm when a RAID 1 member dies


    [27969.398749] sd 5:0:0:0: [sdb] 3907029168 512-byte hardware sectors (2000399 MB) [27969.398749] sd 5:0:0:0: [sdb] Write Protect is off [27969.398749] sd 5:0:0:0: [sdb] Mode Sense: 00 3a 00 00 [27969.398749] sd 5:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [27972.117543] ata6.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [27972.117543] ata6.00: irq_stat 0x48000000 [27972.117543] ata6.00: cmd 60/08:00:ff:7........
  • FUSE/Curlftpfs mount ftp account as drive partition in Linux


    This is a great way to use your ftp server space, for example on your web hosting account (although I believe many hosts don't allow storage like this), but if you have a VPS/Dedicated Server etc.., this would be perfect.  Imagine how easy it is to work with an ftp account that you can just mount as a normal partition or directory in Linux, it would be great for backups etc..   Name curlftpfs - mount a ftp host as a local directory Synopsis........
  • Openvz Enable Most Common iptables modules


    The default options for iptables are very basic.  Here is what you need to do in order to enable them in OpenVZ. 1.) Add the modules to iptables and restart iptables: vi /etc/sysconfig/iptables-config Edit the line as so: IPTABLES_MODULES="ipt_REJECT ipt_tos ipt_TOS ipt_LOG ip_conntrack ipt_limit ipt_multiport iptable_filter iptable_mangle ipt_TCPMSS ipt_tcpmss ipt_ttl ipt_length ipt_state iptable_nat ip_nat_ftp" 2.........
  • Seagate Drive 500GB Drive Dying


    This drive is clearly on the way out, the Kernel knows it but I'm surprised that SMART is not concerned.  I didn't blame Seagate for their past issues until now.  This hard drive has hardly been used and has not even been powered on for a year according to SMART. Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Model Family:     Seagate Barracuda 7200.11 Device........
  • Seagate 7200.11 firmware defect in 500GB, 1000GB (1TB) and 1500GB (1.5TB) Hard Drives


    Seagate Inventory/Firmware Check I heard about this issue a long time ago but never looked into it.  I figured I wasn't affected since my 500GB drives were running for so long.  I've been using Seagate's since 2002 and to this day all of the drives I have are alive from Seagate. *Update the bad news is that I realize one of my 500GB's is about to die, it's not even a year old, but is also not affected by the recall according to Seagate! Seagate Inventory/Firm........
  • Linux AHCI Hotswap Tips - Remember To Reread The Partition Table WITHOUT rebooting


    From the package "parted" you can use the command "partprobe" to re-read the partition table.  I really hate rebooting, and that's what I loved to hear about AHCI motherboards, that they allow hotswap so you don't have to reboot.  But that's only as good as the OS, if the OS does not reload the partition table you won't be able to do anything with that new drive you attached without rebooting.  Yes, even without re-reading the partiton table Linux will........
  • Upgrade Release Kernel Tips


    Upgrade Release Kernel TipsThis is for CentOS 3.1 to 3.8 but the methodology will apply everywhere. I ran into a problem first of all with a non-booting system after running #yum update centos-release It took me to 3.8 and upgraded all the other packages [b:7e931c835d]BUT[/b:7e931c835d] because of some stupid flags enabled in /etc/yum.conf the KERNEL WASN'T UPGRADED SO AFTER BOOTING, WELL IT DIDN'T BOOT OF COURSE :) H........
  • Updating yum repos for DAG /etc/yum.repos.d


    Updating yum repos for DAG /etc/yum.repos.dIn /etc/yum.repos.d [quote:96456b2ab9]Create any file such as "CentOS-Dag.repo" in /etc/yum.repos.d[/quote:96456b2ab9] Add the following to the above file: [code:1:96456b2ab9] [dag] name=Dag RPM Repository For Red Hat Enterprise Linux baseurl=http://dag.atrpms.net/redhat/el$releasever/en/$basearch/dag/ http://dag.freshrpms.net/redhat/e........
  • Trouble connecting between Windows XP and Windows 98 Shares


    Trouble connecting between Windows XP and Windows 98 SharesOk a few things to check for: * Disable all firewalls * Make sure NetBEUI is enabled on both computers * Make sure the Windows XP computer has the name of the computer logged in user of Windows 98 added as an XP user * Add the XP user to anything you want to share That fixed my problem........
  • How to Track Down/Find Cause of Linux high disk iowait/wa


    top - 09:34:12 up 2 days, 20:57,  2 users,  load average: 1.83, 1.99, 2.03 Tasks:  59 total,   2 running,  57 sleeping,   0 stopped,   0 zombie Cpu(s):  0.3%us,  0.0%sy,  0.0%ni,  0.0%id, 99.7%wa,  0.0%hi,  0.0%si,  0.0%st That 99.7% wa is iowait, it means the server is waiting for a process to complete an IO operation or in plain English, there is a delay in........
  • Adventures in pre-paid SIM Cards and data GPRS/Edge/3G in China with China Mobile in Shenzhen, Guangzhou, Shanghai, Beijing and other cities


    This really is a difficult and confusing process for non-Mandarin speakers, but here's what I've done and learned so far: You can purchase an "M-Zone" China Mobile pre-paid SIM Card from almost anywhere but I tried to purchase mine from Suning (a large electronics dealer) hoping they would be able to help me or answer my questions but my plan didn't work out at all.  At Suning once I found someone who spoke some English they gave me the 55 RMB M-Zone China Mobile P........
  • yum error not working rpmdb: mmap: No such device TypeError: rpmdb open failed


    Loaded plugins: fastestmirror rpmdb: mmap: No such device error: db4 error(19) from dbenv->open: No such device error: cannot open Packages index using db3 - No such device (19) error: cannot open Packages database in /var/lib/rpm Traceback (most recent call last):   File "/usr/bin/yum", line 29, in ?     yummain.user_main(sys.argv[1:], exit_code=True)   File "/usr/share/yum-cli/yummain.py&qu........
  • Tyan S2735-8M motherboard/Rackable Systems 1u Server 100mbit NIC not working even when enabled in the BIOS


    I tried everything I could think of, and of course even with the NIC enabled in the BIOS nothing was working.  The light would flash when you plugin the cable for a second, but that's all. Due to another issue I'm about to post about (server is not compatible with 1TB/1000Gig Hard Drives), I updated the BIOS.  I didn't even know the 100mbit NICs were not working until I decided I should test each NIC one by one. I noticed that only 1 server out of........
  • Unlocked iPhone 3GS and firwmare 3.0 battery short low life horrible


    This is pretty bad, ever since my phone has been unlocked the battery life is horrible.  Many others have reported this issue on provider unlocked phones and even jail broken phones.  We're talking issues as bad as losing 1% every 3 minutes which is what I seem to have observed as well. For now I'm going to relock the phone, and hopefully a firmware update will address this issue.  This is very annoying and it seems apparent this is also happening on 3G phones and that........
  • iPhone Backgrounder Adds True and Real iPhone multitasking on jailbroken phones


    Apple crippled the iPhone by not allowing multi-tasking of the non-primary apps.  I use SSH a lot and I don't want to close my session just to check my e-mail, etc, now an app found in Cydia called "Backgrounder" allows just that. Although it's not perfect, we installed the correct one for "3.x" iPhones and hit "Reload SpringBoard" and the hour/circle glass has just been going for minutes. It seems like it installed fine even with the crash t........
  • Samba SMB Error - Server not using user level security and no password supplied. tree connect failed: NT_STATUS_WRONG_PASSWORD


    Server not using user level security and no password supplied. tree connect failed: NT_STATUS_WRONG_PASSWORD That happens when trying to use smbclient to connect to a share.  The weird thing is that I can authnenticate just fine from Windows XP. It is partially my mistake, I forgot this share does have a password.  I've tried authenticating with the correct user and also with "Guest" because this works in Windows.  In Linux I ........
  • Configuring OCFS2 Clustered File System on Debian Based Linux including Ubuntu and Kubuntu


    There's a lot of information and guides on OCFS2 for RHEL and Centos Linux but the package setup and configuration is slightly different and this has thrown some people off. Installing OC2FS You should install the following packages to get started: apt-get install ocfs2-tools ocfs2console Configure OC2FS In RHEL/Centos the main configuration file is located in /etc/sysconfig/o2cb However in Debian based Linux it is located........
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