/ - 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........
  • Linux Kernel USB Export Errors


    4.374647] usb_common: exports duplicate symbol usb_get_dr_mode (owned by kernel) [ 4.403334] usbcore: exports duplicate symbol __usb_get_extra_descriptor (owned by kernel) [ 4.427736] xhci_hcd 0000:00:15.0: xHCI Host Controller [ 4.427844] xhci_hcd 0000:00:15.0: new USB bus registered, assigned bus number 1 [ 4.429040] xhci_hcd 0000:00:15.0: hcc params 0x200077c1 hci version 0x100 quirks 0x01109810 [ 4.429141] xhci_hcd 0000:00:15.0: cache line size of 64 is not sup........
  • hwloc-nox set CPU affinity in Linux


    sudo apt-get install  hwloc-nox Reading package lists... Done Building dependency tree       Reading state information... Done The following NEW packages will be installed:   hwloc-nox 0 upgraded, 1 newly installed, 0 to remove and 530 not upgraded. Need to get 151 kB of archives. After this operation, 453 kB of additional disk space will be used. Get:1 http://archive.ubuntu.com/ubunt........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands


    [root@localhost:~] BootModuleConfig.sh          echo                         host-ind                     nfcd                   ........
  • Linux how to view video card make and exact model


    Normally lspci will show you just like this and would suggest they are exactly the same card: 1a:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/580] (rev e7) 1c:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/580] (rev e7) lspci -vnn is the answer As we can see one is a Gigabyte and the other is an MSI card.  Wha........
  • How to Update Linux /usr/share/misc/pci.ids


    This works with lspci and if it's outdated may not give you the exact manufacturer and device model. For example take these 3 different RX 580's: 1a:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Device 67df (rev e7) 1b:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Device 67df (rev e7) 1d:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Device 67df (rev e7)   You ca........
  • pcimodules and lspci not working alternative solution


    pcimodules no longer works it produces nothing probably because the format of /sys/bus/pci is different. lspci -k doesn't work on older lspci versions. pciutils can be compiled but it won't work if you have an old system and compile on a newer glibc. iteriate through /sys/bus/pci/devices/*/modalias cat /sys/bus/pci/devices/*/modalias pci:v00008086d00001237sv00000000sd00000000bc06sc00i00 pci:v00008086d00007000sv0000000........
  • USB 3.0 PCI x1 Card Review VIA VL805 on Linux Review and Experience


              This is a VIA made VL805 USB 3.0 Chipset with 4-ports and MOLEX powered.  First of all this unit was cheap at about only 9 USD with fast shipping.  My biggest concern was if this was a quality unit and would it really give you full USB 3.0 speeds (some people reported with similar cards that for some weird r........
  • cudaminer freezes Linux Mint taints kernel


    When running cudaminer once it tries to initialize the card the entire screen freezes.  The computer itself is still running but the Xorg is done for, you cannot even switch to another console window and must reboot (even an mdm or Xorg restart does not help). At first cudaminer will give you these errors: stratrum_recv_line failed ...retry after 15 seconds GPU #0: Geforce 210 with compute ca........
  • 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........
  • Nvidia Linux Card not working due to LSI 9200/SAS2008 IRQ conflict


    At first my BIOS said the card may not work right because there is no more option ROM space. I disabled the Option ROM for both LSI 1068 and 2008 chipsets, Network Boot ROM and most other PCI slots, Serial Port, etc... and the message went away but the card still does not work properly. But it still cannot initialize the card properly (does not work): [   33.943272] NVRM: This PCI I/O region assigned to your NVIDIA device is invalid:........
  • SAS2008 LSI 9200-E Linux Upgrade Flash Firmware with sas2flash


    Download from here http://www.avagotech.com/products/server-storage/host-bus-adapters/sas-9200-8e#downloads   sudo Installer_P20_for_Linux/sas2flash_linux_i686_x86-64_rel/sas2flash -listall LSI Corporation SAS2 Flash Utility Version 20.00.00.00 (2014.09.18) Copyright (c) 2008-2014 LSI Corporation. All rights reserved   &nbs........
  • Virtualbox errors on Ubuntu/Debian/Mint


      The solution was to reinstall the vbox dkms package and do a manual modprobe of the modules it makes. I never sorted out the unable to start due to the USB issue, I did have the guest additions installed but the only way to boot was to change the pointing device from USB to PS2 and then to disable the USB controller (if your pointing device is set as USB, disabling USB will not work because it will re-enable by default when it sees your pointing device is USB, this is w........
  • Dell CS24-NV7 lspci dmidecode info


    0000:00:00.0 RAM memory: NVIDIA Corporation MCP55 Memory Controller (rev a2) 0000:00:01.0 ISA bridge: NVIDIA Corporation MCP55 LPC Bridge (rev a3) 0000:00:01.1 SMBus: NVIDIA Corporation MCP55 SMBus (rev a3) 0000:00:02.0 USB controller: NVIDIA Corporation MCP55 USB Controller (rev a1) 0000:00:02.1 USB controller: NVIDIA Corporation MCP55 USB Controller (rev a2) 0000:00:05.0 IDE interface: NVIDIA Corporation MCP55 SATA Controller (rev a3) 0000:00:05.1 I........
  • Dell CS24SC Server Info


    Dell CS24SC Info 0000:00:00.0 Host bridge: Intel Corporation 5100 Chipset Memory Controller Hub (rev 90) 0000:00:02.0 PCI bridge: Intel Corporation 5100 Chipset PCI Express x8 Port 2-3 (rev 90) 0000:00:03.0 PCI bridge: Intel Corporation 5100 Chipset PCI Express x4 Port 3 (rev 90) 0000:00:04.0 PCI bridge: Intel Corporation 5100 Chipset PCI Express x16 Port 4-7 (rev 90) 0000:00:05.0 PCI bridge: Intel Corporation 5100 Chipset PCI Express x4 Port 5 (rev 90)........
  • Dell CS10-F1D Server Info lspci Linux specs


    0000:00:00.0 Host bridge: Intel Corporation 5000P Chipset Memory Controller Hub (rev b1) 0000:00:02.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x8 Port 2-3 (rev b1) 0000:00:03.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x4 Port 3 (rev b1) 0000:00:04.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x8 Port 4-5 (rev b1) 0000:00:05.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x4........
  • Linux Kernel EDAC errors EDAC MC0: UE row 0, channel-a= 0 channel-b= 1 labels "-": NON-FATAL recoverable (Branch=0 DRAM-Bank=0 Buffer ID = 0 RDWR=Read RAS=0 CAS=0 NON-FATAL recoverable Err=0x800 (Non-Aliased Uncorrectable Patrol Data ECC))


    I'm not sure why I'm getting these but all memory modules are the exact same and all passed memtest successfully although they are ECC.  I've heard that ECC RAM can't be tested as well and the kernel seems to indicate they are non-fatl recoverable errors.  I wonder if the BIOS has aggressive RAM timing or maybe the controller or motherboard is bad.   [   12.716515] EDAC MC: Ver: 2.1.0 [   12.717771] EDAC MC0: Giving out device to........
  • 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........
  • OpenVZ mismatched kernel and dev when compiling.


    ./configure ./configure: line 91: cd: /lib/modules/2.6.32-042stab084.25/build: No such file or directory Error: kernel version not found. Please make sure your kernel is configured. dr-xr-xr-x.  4 root root   4096 Feb 21 06:13 .. lrwxrwxrwx   1 root root     45 Feb 21 06:13 build -> ../../../usr/src/kernels/2.6.32-042stab084.25 drwxr-xr-x   2 root root   4096 Feb 12 20........
  • 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........
  • Dell SAS 6/ir Cards are just LSi 1068E cards


    02:00.0 SCSI storage controller: LSI Logic / Symbios Logic SAS1068E PCI-Express Fusion-MPT SAS (rev 08) 03:00.0 SCSI storage controller: LSI Logic / Symbios Logic SAS1068E PCI-Express Fusion-MPT SAS (rev 08) Basically these cards are a stripped-down version of Dell Perc 6/i only  they (SAS 6/ir) support JBOD. The Dell Perc 6/i are basically useless because it doesn't have JBOD support and requires software or BIOS commands to add or remove........
  • 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........
  • Dell Perc 6/i SATA benchmarks without battery


    The results are not bad, the Hitachi performs the same as it does in a SATA2 motherboard.  However, the 2TB is much different, on a similar 2TB Toshiba I get about 198MB/s on a different motherboard vs the 2TB Hitachi which should produce similar results. This Dell Perc 6/i is on a PCI x8 riser card and is connected to a 12-port backplane. Adapter #0     Enclosure Device ID: 32 Slot Number: 0 Enclosure position: N/A De........
  • Dell Perc 6/i Restore BIOS/Bricked Solution Guide Howto


    I bricked one of my cards by following a guide from UNRAID. Step #1 from them wipes out the BIOS, but guess what?  The step where you restore the BIOS should have been done first, which is sas2flash but no version supports or is able to find my Perc 6/i.  So now I'm a bit stuck. I tried using megarec but it's funny that it can wipe the BIOS but can't forcefully reload it: megarec -writesbr 0 mpt2sas.rom Supports 1078 control........
  • 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.........
  • 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........
  • pxe-32 tftp open timeout


    pxe-32 tftp open timeout   The solution was to enable tftp in xinetd with "chkconfig tftp on". See the troubleshooting below:   chkconfig --list NetworkManager     0:off    1:off    2:off    3:off    4:off    5:off    6:off acpid              0:off&n........
  • eth0 changed to eth1 or eth2 and the solution to fix it


    If you move your hard drive(s) around to other computers/servers, you'll find that your eth0 keeps getting higher, the first time it will become eth1 and then eth2 etc and even higher if your server has dual or quad NICs.  The reason is that udevd basically assigns eth0 tot he first NIC it finds and remembers it, if it encounters a NIC with a different MAC, it assigns it one higher (eg. eth1). See the example below, I have eth2 now so how do I fix it?........
  • Centos 6 RTL8111/8168B r8169 link up and down error solution/fix


    02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 03) For whatever reason it seems the r8169 driver that ships and has shipped with most Linux distros for years is still flawed and does not work properly on these cards, causing 100mbit connectivity when it should be 1gbit and even worse, causing random network dropouts.  The r8169 driver in Linux kernels is simply not meant to be used on th........
  • Nearly 100% CPU Usage from processes called dma0chan0 dma0chan1 dma0chan2 dma0chan3


    I never started these processes but they are from a custom based bootable Linux I've made and I've never seen this behavior on other machines or even with the same machine using different kernels.  These processes seemed to spawn on their own and I have no idea why and even worse why the CPU usage is so high? Here's the output from top:   907 extaudit  30  10     0    0    0 R 90.7  0.0 ........
  • 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........
  • Linux Ubuntu Nvidia GT430 Lockups/Errors/Freezes NVRM: os_schedule: Attempted to yield the CPU while in atomic or interrupt context


    I'm running Ubuntu 10.10 with Asus NVIDIA GT430 2.6.35-32-generic-pae #65-Ubuntu SMP Tue Jan 24 14:06:16 UTC 2012 i686 GNU/Linux Nvidia binary driver: 260.19.06 The screen sometimes completely freezes and locks up or everything starts going very slow: [1903398.100007] NVRM: os_schedule: Attempted to yield the CPU while in atomic or interrupt context [1903402.373210] NVRM: Xid (0001:00): 53, CMDre 00000000 00000080 00000000 00000005 00........
  • Xen non-HVM container won't work/boot anymore


    One of my test Centos 5 containers was on a partition that filled up and it threw all sorts of errors and stopped responding but now I can't boot it again anymore. All the console shows is the Linux Penguin on the top left corner and the xm console says "usbcore: registered new driver hub" and has halted there. Centos 5 Xen container stuck/frozen won't boot on "usbcore: registered new driver hub" Another great way of troubleshooting is booting fro........
  • Kernel linux-2.6.39 In file included from drivers/block/cciss.c:1015: include/asm-generic/pci-dma-compat.h: In function `cmd_special_free': drivers/block/cciss.c:196: sorry, unimplemented: inlining failed in call to 'cciss_tag_discard_error_bits': fu


    In file included from drivers/block/cciss.c:1015: include/asm-generic/pci-dma-compat.h: In function `cmd_special_free': drivers/block/cciss.c:196: sorry, unimplemented: inlining failed in call to 'cciss_tag_discard_error_bits': function body not available include/asm-generic/pci-dma-compat.h:25: sorry, unimplemented: called from here make[2]: *** [drivers/block/cciss.o] Error 1 make[1]: *** [drivers/block] Error 2 make: *** [drivers] Error 2........
  • 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.........
  • Linux Kernel Freeze/Hang during boot on io scheduler cfq registered (default)


    You'll see the following and the boot process will freeze: io scheduler noop registered io scheduler anticipatory registered io scheduler deadline registered io scheduler cfq registered (default) I have struggled with this issue on vari........
  • VirtualBox/VBOX Centos 5.5 Installation Kernel Freeze Problem "NET: Registered protocol family 2" And Solution


    NET: Registered protocol family 2 The above is the last thing that I ever saw, I tried pci=routeirq etc.. and it wouldn't work. The solution is to enable IOAPIC in the VBOX Settings Just enable "IOAPIC" in the settings for your Centos Guest and you'll find the kernel boots just fine.  I wonder if a physical system might stall in this same way if the BIOS has IOAPIC disabled which many people do as a troubleshooting method.  ........
  • Realtek r8169 1gbit/1000mbit NIC/Ethernet Goes Down/Halts on Large File Transfer/Heavy Network Usage


    This is obviously a bug in the r8169 kernel module and it seems to affect a lot of people.  I upgraded to the latest kernel and hope this won't happen anymore, as it is a very serious error.  This is especially serious for those who are running servers with this chipset, who can afford for the NIC to randomly go off-line for no apparent reason?   [655548.189113] type=1505 audit(1277067560.902:5): operation="profile_load" name="/usr/bin/freshclam&q........
  • How To Set DHCP/Static IP Address in Centos/RHEL/Fedora & Debian/Ubuntu/Kubuntu/MEPIS Set DHCP/Static IP Address


    Basically the two main types of distros are Debian and RHEL/Centos based.  I'm just going to give a quick overview of how the configuration of IP interfaces works in Debian/Centos based distros. *Just one thing to remember, when setting IPs statically you have to manually specify a DNS server in /etc/resolv.conf (since DHCP is what normally does it automatically) Debian/Ubuntu/Kubuntu/MEPIS The IP (DHCP &........
  • Compaq V2405CA Laptop - Unixbench Performance Test


    Here are the results, it is Sempron 3000+ AMD Mobile, 500Gig HDD, 512MB RAM with shared ATI Radeon graphics.      #    #  #    #  #  #    #          #####   ######  #    #   ####   #    #    #    #  ##   #  #   #  #&nb........
  • Linux Kernel Compilation (Intel(R) 82575/82576 PCI-Express Gigabit Ethernet support ) Error - drivers/net/igb/igb_main.c: In function `igb_up': make[3]: *** [drivers/net/igb/igb_main.o] Error 1


    Linux Kernel v2.6.30.3 102220 blocks   CHK     include/linux/version.h   CHK     include/linux/utsrelease.h   SYMLINK include/asm -> include/asm-x86   CALL    scripts/checksyscalls.sh   CHK     include/linux/compile.h   CC      drivers/net/igb/igb_main.o drivers/net/igb/igb_main.c: In function `igb_up':........
  • 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........
  • OCFS2 crash


    When trying to even cd or ls the mounted OCFS2 partition it crashes.  I think this is a combination of VMWare Server's problem and the way I mounted and symlinked to it. More than anything this shows the problem and lack of forsight with VMWare, but also that OCFS2 is easily crashed if you do strange things. Output of /var/log/messages for OCFS2   Apr 10 15:57:45 localhost kernel: [84331.691258] Modules linked in: vmnet vmci vmmon ocfs2_stac........
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