• Cisco Unified Communications Manager / CUCM IP 8.6,10,12 Install Error Solution


    Install Errors on Version 12: This error happened on QEMU emulator version 2.11.1 pve-qemu-kvm_2.11.1-5 on Proxmox/Debian but installing on QEMU.12 on Centos 6 did not produce the error. *Update it is not related to the OS or QEMU version. This happened in Centos 6 too after a second install. What really causes this even though you successfully install........
  • Ubuntu Debian Mint Linux SSHD OpenSSH Server Not Starting After Reboot Solution


    If you get error messages like this it is usually because /var/run/sshd does not exist. root@userbox:/# service sshd status ‚óŹ ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enab Active: failed (Result: start-limit-hit) since Wed 2019-04-10 02:24:44 EDT; 1 Process: 511 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=255)........
  • gsmartcontrol for Windows to Check the SMART S.M.A.R.T status


    gsmartcontrol is a free tool that let's you see the status of the SMART parameters so you can check things like temperature, reallocated sectors, bad sectors etc.. to give you a better idea of your drive health. Download it here. gsmartcontrol is a very useful tool in Windows to check your HDD / Hard Drive health status. In my experience you should NEVER trust that everything is OK just because SMAR........
  • ssh reverse proxy to enable remote access behind a LAN and firewall


    So say you are behind a typical NAT/LAN setup whether at home, work or while travelling. What if you have a computer or server that you need to connect to from the outside? Yes you could use a VPN but a quick and dirty, temporary and secure way is to use SSH's Reverse Tunneling Proxy feature. Requirements On the remote ssh server host you need the GatewayPorts option enabled in sshd_config (be........
  • X11 SSH Linux Forwarding Error


    Jan 30 17:16:10 localhost sshd[25385]: error: Failed to allocate internet-domain X11 display socket. The solution for me on the server side was the following in sshd_config: AddressFamily inet *Remember to restart sshd and also reconnect from the client side. Ihad all the normal X11 settings on the server but it just stopped........
  • Debian 9 SSH root password authentication failure password not working problem / solution


    In Debian a lot of times SSH disables the root user to login by password by default. This means you will get an authentication failure as if you typed in the wrong password. The logs also indicate the password is wrong but what is often the case is in the config file Check /etc/ssh/sshd_config cat /etc/ssh/sshd_config|grep -i permitrootlogin Make sure it says: PermitRootLogin yes If not change it and restart SSH........
  • VirtualBox How To Add iSCSI Storage using VBoxManage


    #to show all VBoxManage list vms #show ONLY running vms VBoxManage list runningvms VBoxManage storageattach test --storagectl "SATA" --port 0 --device 0 --type hdd --medium iscsi --server 192.168.1.91 --target "iqn.2018-12.local.abcrandom.target:sdb" --initiator "iqn.1982-01.ca.bla.tld:abc123" --t........
  • Python and BeautifulSoup4's BS4's Decompose Method To Remove Unwanted Inner Tags


    < a href="/Products/MX72244"> < span class="c-shca-icon-item__body-name-brand"> ADATA < / span> &nbs........
  • 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........
  • Proxmox error uploading an iso solution


    Error 0 occurred while receiving the document root@vh1:/var/tmp# wget http://mirror.compevo.com/proxmox/proxmox-ve_5.2-1.iso --2018-08-30 16:27:37-- http://mirror.compevo.com/proxmox/proxmox-ve_5.2-1.iso Resolving mirror.compevo.com (mirror.compevo.com)... 103.25.61.44 Connecting to mirror.compevo.com (mirror.compevo.com)|103.25.61.44|:80... connected. HTTP request sent, awaiting response... 200 OK Length: 641517568 (612M) [application/o........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands


    [root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........
  • Hard Drive Serial Number Examples


    The reason for this article is because a lot of us don't physically see our hard drives they are often remote in a datacenter etc and the actual serial number we see in SMART is not enough to check for some manufacturers. A good example is our first one the Toshiba === START OF INFORMATION SECTION === Device Model: TOSHIBA DT01ACA200 Serial Number: 33FMDW4AS........
  • Prevent SSH Bruteforce and Hacks By Disabling Password Authentication


    One simple way to keep your server public but almost impossible to hack via SSHis to disable password authentication over SSH. This means the only way in is via your own private key that only you should have. Edit your /etc/ssh/sshd.conf file Set this option PasswordAuthentication no Restart your SSH server. service sshd restart ........
  • Linux How To Clone One System Harddrive to another remote system


    The easiest way is to use SSHand DD or a combination of netcat. SSHwill be a little slower due to encryption but is the most secure way (on two older systems the average clone speed is about 40-50MB/s). This is also OS independent as it doesn't matter what the source OS is because you are literallly cloning the drive so you retain the partition table and settings. Clone HDD using SSH and DD........
  • Ubuntu/Debian/Linux won't boot and drops to Busybox shell after cloning HDD with dd


    I don't recall having this issue in the distant past but nowadays at least Debian seems to be very picky about this. I used dd to copy one hard drive to another and tried booting it. Everything seemed fine with grub working but each time it would drop to the busybox shell. There is no particular error so this is misleading. Normally the first things you would check are to make sure your fstab is correct (that the UUID is correct)and that you've updated grub.&........
  • Authentication refused: bad ownership or modes for directory /home/user SSH Public Key Authentication Failed Solution


    First of all I got this error after accidentally messing up my usergroup by using usermod -G user group When I would login using SSHkeys it would fail: sshd[2020]: Authentication refused: bad ownership or modes for directory /home/one No worries, the fix is simple! chmod g-w /home/use........
  • M2Crypto.SSL.Checker.WrongHost: Peer certificate subjectAltName does not match host, expected fedora-archive.ip-connect.vn.ua, got DNS:mirror.ip-connect.vn.ua


    You are using Centos 5 which is deprecated so nothing in yum will work until you follow this post to use the vault: http://realtechtalk.com/Centos_59_Working_Vault_Repo_file-1921-articles yum update Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * epel: fedora-archive.ip-connect.vn.ua Traceback........
  • Disable SSH Password Authentication to Increase Security and Harden SSH Linux Unix Server Ubuntu Mint Centos Debian


    Just a note before you do this you should have a sure, guaranteed way into the system such as local, KVMor preferably publickey making bruteforce SSH absolutely impossible since there is no password to bruteforce and even if someone knew the password they wouldn't be able to login except from the local console (presumably you should make sure no one unauthorized has physical access). 1. Edit /etc/ssh/sshd_config Find the section like this:........
  • Intel NUC Lower Power Green Computing Boxes Review/Comparison of J3160 and J3455 Models


    Intel NUC J3455 vs Vorke V1 J3160 Both are excellent units but the J3160 is nicer if you require even lower power usage (6W vs the Intel 10W). The price is attractive on the Vorke V1 as well. It's been said that the Intel J3455 NUC has a buggy BIOS and some other issues that require attention. The Intel J3455 is still nice because it has 2 RAMslots but it does get hotter due to lack of fan. The Vorke V1 runs cooler, uses less power an........
  • kdenlive titles/text renders as white screen when using .sh script


    When using the .sh script the rendering doesn't work after an upgrade of related packages to kdenlive. kdenlive (kdenlive:amd64 (4:17.04.1+git201705191233~ubuntu16.04.1)) with affine or composite transitions was fine but is now broken during the time of transition it is just a white screen. The previous version was fine: kdenlive:amd64 (4:17.04.1+git201705191233~ubuntu16.04.1 But now I can't find it or install it:........
  • 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 ........
  • Migrate Centos 7 from Single HDD to mdadm RAID 10 array:


    Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler! Hint do not use grub2-install! One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting The normal way will not work here if your Centos was using UEFI. Newer systems use it by default. The easiest way to check is to do an fdisk -l if your sy........
  • USB 3.0 External HDD Enclosure Seagate UAS problems - [sdd] tag#1 CDB: Write(16) 8a 00 00 00 00 01 70 04 08 68 00 00 00 08 00 00


    This is a 8TB Seagate external USB 3.0 device apparently newer kernels use a module called "UAS" instead of "USB Storage" which causes issues as a lot of devices are not properly supported in UAS mode by the kernel driver. The solution some say is to disable UAS specifically for your USB device but I'd rather just disable UAS altogether. Solution blacklist UAS: *do not do this it does not work and just causes your USB 3.0........
  • 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........
  • sshd[10470]: Authentication refused: bad ownership or modes for directory /root


    This can be a case of bad permissions or modes as the error says. Normally one would assume permissions but often a script may change ownership of /root to something else. This was the case half the time I've encountered this. So in short make sure ownership is correct chown -R root.root /root........
  • fdisk wq causes hung process


    I created a new partition table on a newly plugged in device and it caused fdisk to hang (even force kill does not work). It also may be a bad drive or some other issue because fdisk -l hangs after the first 2 HDDs (totaly of 8 HDDs on this system): [1232879.903596] INFO: task fdisk:27176 blocked for more than 120 seconds. [1232879.903607] Tainted: P&nbs........
  • 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........
  • VBOX/Virtualbox how to resize the disk file image vdi


    VBoxManage modifyhd "my.vdi" --resize 60000 Note the above will resize my.vdi to 60,000MB........
  • Ubuntu/Debian OpenVZ Template Problems No Networking and SSH not starting


    It all comes down to a bug essentially where you are running an older kernel that doesn't support the newer Debian templates. The solution is to update your OpenVZ kernel. Here are some symptoms of the problem/lack of kernel support: Ubuntu Template 12.04 requires a manual network start: service networking start sshd will not start: /usr/sbin/sshd PRNG is not seeded mknod /dev/random c 1 8........
  • 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........
  • grub> setup (hd1) Checking if "/boot/grub/stage1" exists...


    It freezes on"grub> setup (hd1) Checking if "/boot/grub/stage1" exists..." Basically it looks like the partiion table is corrupt or the data/files are not there.........
  • Centos installing grub problems suspect gpt problem


    grub> root (hd0,0) root (hd0,0) Filesystem type is ext2fs, partition type 0xfd grub> setup (hd0) setup (hd0) But if you do: root (hd1,0) setup (hd1) it does work, I think hd0/sda had a GPT partition that was not removed properly (what I did was just dd bs=512 count=1 the partition table from another drive since the partition table should be identical). Checking if "/boot/grub/........
  • mdadm real example of recovery and rebuilding of the array on Centos 6


    In this example we have 2 drives in a RAID array and /dev/sdb is the one that failed. /dev/sda1 is also the /boot partition which we tell grub to install on /dev/sdb eg install root (hd0,0) /dev/sda1 on the new drive /dev/sdb (hd1) First copy the partition table from /dev/sda to /dev/sdb dd if=/dev/sda of=/dev/sdb bs=512 count=1 Run partprobe to detect the new partition table partprobe........
  • Centos 6 how to guide convert LVM non-RAID into mdadm 1/10 RAID array live without reinstalling


    Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason. Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to? In some cases on a remote system you can't easily reinstall without physical or KVM access. So in this case you add a second physical or disk or already ha........
  • openvz yum problem Centos 6.5 cannot find file on mirror:


    #solution Edit /etc/yum.repos.d/openvz.repo For the first two entries comment out #mirrorlist and uncomment #baseurl and then it worked openvz yum problem Centos 6.5 cannot find file on mirror: yum update Loaded plugins: fastestmirror Determining fastest mirrors * openvz-kernel-rhel6: mirrors.ustc.edu.cn * openvz-utils: mirrors.ustc.edu.cn base ........
  • 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........
  • grub cannot install or boot from mdadm RAID 10 array


    root (hd2,1) Filesystem type unknown, partition type 0x83 grub> root (hd2,2) root (hd2,2) Filesystem type is ext2fs, partition type 0x83 grub> setup (hd2) setup (hd2) Checking if "/boot/grub/stage1" exists... no Checking if "/grub/stage1" exists... no #weird thing about grub is that the drive you enter is considered hd0 For example when booted fu........
  • ssh session and port forward or reverse port matching or assocation howto


    Use netstat with the -anpe option. The e option shows the inodes and I do not know if it will always work or if it was by fluke but I was dealing with dozens of SSHsessions and needed to know which session was related to which forward (the PIDs of the SSHand SSHD did not match etc...) Notice the "59560675" and "59560762" those are almost identical, if you find two sets that are nearly identical except for the last 3 digits they may match (in my ca........
  • 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........
  • Dell CS24,FS12 NV5 and NV7 1U Server Information & Parts


    Motherboard: Gigabyte GA-3CESL: http://b2b.gigabyte.com/products/product-page.aspx?pid=2658#dl Dell Part Numbers for the motherboard: R1232 R1232L R2232S SERVER MOTHERBOARD GENUINE 408P9 CN-0408P9 GA-3CESL Manual Download here RAMSlots: 16 (8 controlled by each CPU) RAMType: DDR2 ECC 5300P........
  • 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 Ididn'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 Ibelieve is be........
  • Howto Convert Xen Image to KVM


    #count=10000 makes an image of 10000MB make sure your image is at least the same as your existing dd if=/dev/zero of=yourimage.img bs=1M count=10000 # losetup -fv newimage.raw # fdisk -cu /dev/loop0 # kpartx -a /dev/loop0 # dd if= of=/dev/mapper/loop0p1 # e2fsck -f /dev/mapper/loop0p1 # resize2fs /dev/mapper/loop0p1 # a lot of guides tell you to edit /etc/fst........
  • 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........
  • [Hardware Error]: CPU:0 MC4_STATUS[-|CE|MiscV|-|AddrV|CECC]: 0x9c054c84011c011b [Hardware Error]: cache level: L3/GEN, tx: GEN, mem-tx: RD [Hardware Error]: Northbridge Error (node 0): L3 data cache ECC error.


    This server has been running for weeks without issue, it's currently only using 1 of 2 CPUs as it is running in the office as a test bed (mainly due to the handle 12 bay storage/great for testing HDDs). The errors below seem to mainly be from AMD CPUs, it's only happened a single time and in the days since Igot that error it hasn't occurrred. Interestingly enough /proc/cpuinfo still shows all 4 cores of the CPU (Opteron 2373 Quadcore HE) and the functionality doesn't seem........
  • 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........
  • 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........
  • VBoxSVC uses 100% CPU on Virtualbox Host running Ubuntu


    I haven't updated VBOX in ages but have never seen this issue and it has my CPU running at 100C. Manually/forcefully killing the process does not work with "kill -kill 3892". I've closed the VBOXManager and everything else related to it. This did seem to happen around the time I ran VBoxManage clonehd and it failed, the terminal issue locked up and also never wrote a byte of anything. I forced killed the VBoxManage and tried to remove &........
  • SSH Can't Login/Hang


    Client Log OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: Connecting to 192.168.1.253 [192.168.1.253] port 22. debug1: Connection established. debug1: permanently_set_uid: 0/0 debug1: identity file /root/.ssh/identity type -1 debug1: identity file /root/.ssh/id_rsa type 1 debug1: identity file /root/.ssh/id_d........
  • Toshiba Hard Drive Warranty RMA Serial Number Info


    Here's the link to the warranty checker and from there you can also create an RMA: https://myapps.taec.toshiba.com/myapps/admin/jsp/webrma/addRequest1NoLogin.jsp Note that the serial# shown in SMART is not complete as is the case for many other brand sof HDDs. For example a 2TB Toshiba shows the following Serial Number in SMART: Device Model:........
  • Bad Hard Drive Slows Down Computer


    Here's a proven example of what a bad hard drive can do, it was technically functioning OKin 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 1TBHitachi 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........
  • Strange SATA error code when turning on HDD/Hard drive - [1433128.139339] sd 5:0:1:0: [sde] Unhandled error code [1433128.139343] sd 5:0:1:0: [sde] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK [1433128.139348] sd 5:0:1:0: [sde] CDB: Read(10):


    [1433128.139339] sd 5:0:1:0: [sde] Unhandled error code [1433128.139343] sd 5:0:1:0: [sde] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK [1433128.139348] sd 5:0:1:0: [sde] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [1433128.139360] end_request: I/O error, dev sde, sector 0 [1433128.139410] sd 5:0:1:0: [sde] Unhandled error code [1433128.139414] sd 5:0:1:0: [sde] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK [1433128.139420] sd 5:0:1........
  • badblocks in Linux to check/verify if a hard drive/HDD is good or bad


    I like badblocks and don't know a better more reliable way of checking the drive. If there are no errors from badblocks and dmesg doesn't produce any SATA related errors, the drive should be good (for now at least). I also prefer to do read and write mode, yes it takes ages but it is really the best way of doing it. This gives me the most confidence in knowing that a drive, especially a new one is at least OK at the moment. To test in read only mode........
  • How to install GRUB to the MBR of a disk image.


    cat | grub --device-map=/dev/null Now pay close to the attention of the beginning. Type: "device (hd0) VPS.img" this is telling what hd0 will be to GRUB and we're telling it the disk image file "VPS.img" in the current directory is hd0, you can specify alternate paths and image names of course. GNU GRUB version 0.97 (640K lower / 3072K upper memory) [ Minimal BASH-li........
  • mdadm how to add a device to an array after a failure


    This array is a RAID 1 and in this case 1 of the 2 drives failed (a WD drive and I've found them to be the weakest and most unreliable of any brand and are easily damaged/DOA when shipping them). mdadm --manage /dev/md0 --add /dev/sdb1 The above assumes the array you want to add to is /dev/md0 and the device we are adding is /dev/sdb1 *One thing to remember is to make sure the partition you are adding is the correct size for the array. You can also g........
  • VirtualBox How to Resize Hard Drive


    VBoxManage modifyhd XP.vdi --resize 15000 VBoxManage modifyhd XP.vdi --resize 15000 0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100% That resizes the virtual hard drive image "XP.vdi" to 15000MB instantly. I doubt this is safe to do while the VM is running and I'm not sure if it would attempt it still but turn the VM off first to be safe. I also notice in the VBOX GUI that it still shows the orig........
  • 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........
  • Hitachi HDD/Drive RMA Process Experience


    The first Hitachi Deskstar 2TB 5K3000 drive I bought arrived DOA for whatever reason (not recognized by the BIOS or OS). Perhaps it was shipping since I bought only 1 hard drive. When I bought 4 through another Vendor, all 4 checked out fine. I was worried about the RMA process because a lot of people have complained about Hitachi taking weeks to send out their hard drive and almost implied the warranty is useless. I'm happy to report that my experience was great a........
  • 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........
  • GRUB Solution to error "Error 6: Mismatched or corrupt version of stage1/stage2"


    GNU GRUB version 0.97 (640K lower / 3072K upper memory) [ Minimal BASH-like line editing is supported. For the first word, TAB lists possible command completions. Anywhere else TAB lists the possible completions of a device/filename.] grub> root (hd1,0) Filesystem type is ext2fs, partition type 0xfd grub> setup........
  • Hitachi 2TB HDS5C3020ALA632 drive DOA


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    sshd[9217]: Authentication refused: bad ownership or modes for file /root/.ssh/authorized_keys I made sure the entire .ssh subdir is owned by the user root (this is root's account); chown -R root.root .ssh chmod 600 .ssh/authorized_keys but it still doesn't work and gives me the same message sshd[7339]: Authentication refused: bad ownership or modes for directory /root chmod 700 /root........
  • Ubuntu 9.04 Crash


    CPU/Kernel/MB/RAID problem? Jan 5 12:45:05 testbox kernel: [653298.890004] BUG: soft lockup - CPU#0 stuck for 61s! [hal-acl-tool:4168] Jan 5 12:45:05 testbox kernel: [653298.890005] Modules linked in: vmnet vmci vmmon binfmt_misc drbd video output input_polldev ocfs2_stackglue ocfs2_dlmfs ocfs2_dlm ocfs2_nodemanager configfs k8temp hwmon_vid lp snd_hda_intel snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi........
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    VMWare bridged adapter not working: Message from system: The network bridge on device vmnet0 is not running. The virtual machine will not be able to communicate with the host or with other machines on your network. Failed to connect virtual device Ethernet1. I'm not sure how to fix this but one of the issues is that my eth0 became eth1 after moving my hard drives to a new motherboard. I have run the vmware-config.pl but this did not resolve the issue.........
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    I've never understood how to enable and disable services for different run levels in Debian based distros, it's just weird, annoying and doesn't make sense. I much prefer chkconfig from RHEL. Just install the package called 'rcconf' and be done with it. rcconf makes things easy for you. apt-get install rcconf Reading package lists... Done Building dependency tree Reading state information... Done........
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    www.antec.outervision.com/index.jsp I found that wattage/power consumption tool to be very useful, especially when you're worried that you're hitting the Power Supply's limit. You'll see very quickly that different CPU's, Graphics, Cards, HDDS use a wide range of energy. That tool can help you choose a build that won't stress or go over the maximum limits of your Power Supply.........
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    I successfully created a single RAID 1 partition which includes /boot inside it and my root directory through the Debian installer. It said GRUB installed successfully but when I try booting the OS it seems GRUB can't read anything. When trying to boot from GRUB GRUB Loading stage 1.5. GRUB loading, please wait... Error 2 I get "Error 2" when trying to boot Debian. I also notice from a LiveCD that........
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    This is a very simple solution, but most guides out there make you login twice (once to scp the key) and once to put the key in authorized_keys. There's no need for that. If you don't already have a ~/.ssh/id_rsa.pub just type "ssh-keygen -t rsa" and keep hitting enter until it's done :) Just use this code to easily enable passwordless login with SSHD key=`cat ~/.ssh/id_rsa.pub`;ssh user@192.168.5.25 "echo $key >> ~/.ssh/auth........
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    Before we start I take no responsibility for this, you should have a backup and if you make a mistake during this process you could wipe out all of your data. So backup somewhere else before starting this as a precaution, or make sure it's data you could afford to lose. The RAID 1 Setup (Hardware Wise) I've already setup my 2 x 1TB (Seagate) drives with identical partitions, make sure your new hard drive (the empty one) is setup like your curr........
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  • Clone any OS partition perfectly


    Clone any OS partition perfectlyIn one box I needed to copy the boot partition to another disk while retaining the MBR and other data. I simply ran this command: [code:1:1b1ff110ca]dd if=/dev/hda1 of=/dev/hdb1[/code:1:1b1ff110ca] [b:1b1ff110ca]if[/b:1b1ff110ca] = source patition [b:1b1ff110ca]of[/b:1b1ff110ca] = destination partition Here's an interesting article on it http://www.rajeevnet.com/hacks_hints/os_cl........
  • GRUB Boot FreeBSD


    GRUB Boot FreeBSD[code:1:a7050277b7]title FreeBSD 6.0 root (hd0,2,a) kernel /boot/loader[/code:1:a7050277b7] Just insert the above code into GRUB's [b:a7050277b7]menu.lst[/b:a7050277b7] and make sure you set the root path correctly. [quote:a7050277b7]Let's quickly explain what the root (hd0,2,a) means: *hd0 stands for the primary master drive *2 stands for partition 3 *a stands for the........
  • SSH automatic login without password


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  • Mount Linux ext2 file system


    Mount Linux ext2 file systemNormally in Linux you could mount ext2 or ext3 etc... like this: mount -t ext2 /dev/hda1 /mnt/hda1/ In FreeBSD the difference is of course the disk naming conventions (hda1 would be known a /dev/ad0s1): To mount ext2 in FreeBSD just type: mount -t ext2[b:68c16c60bf]fs[/b:68c16c60bf] /dev/ad0s1 /mnt/ad0s1........
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    Updated to Version 3.8 and can't loginSSHD accepts my password but then hangs at "Last login: Wed Sep 13 21:30:02 2006 from" This occurred during a yum update after upgrading my release, installing the new kernel and rebooting. I got kicked out of sshd after seeing the following during yum update: telnet 100 % done 85/476 tux 100 % done 86/476 ntsysv 100 % done 87/476 rpmdb-redhat 94 % done 88/476........
  • Need identd for port 113 ? Install authd


    Need identd for port 113 ? Install authdyum install authd Happy identing :)Actually it's not that simple. It installs as an "xinetd" service and is disabled and turned off by deafult. To enable it run: [code:1:8c94df8319] chkconfig --level 3 auth on service xinetd restart [/code:1:8c94df8319] This will set identd aka authd to start by default. service xinetd resta........
  • How to compile in Windows/DOS


    How to compile in Windows/DOSMingW is a free compiler project so start here: http://www.mingw.org/download.shtml#hdr2 I downloaded the core GCC compiler: http://prdownloads.sf.net/mingw/gcc-core-3.4.2-20040916-1.tar.gz?download But it's missing even the standard C runtime libraries like "stdio.h"! You may also need to add environment variables from the DOS command line. Here is a simpl........
  • sed is great for pattern matching or retrieving lines


    sed is great for pattern matching or retrieving linesHere is a cool example Say you type df: The output would be something like: [quote:3bb8d51437]Filesystem 1k-blocks Used Available Use% Mounted on /dev/hda2 1712432 1206664 418780 75% / /dev/hda1 31201 10505 19085 36% /boot none 30932 0 30932 0% /dev/shm [/quote:3bb8d51........
  • GRUB "Error 2: Bad file or directory type" 0.97 won


    You can see the problem below, GRUB recognizes my hard drive and sees the partitions but cannot access them. This is from the GRUB boot disc I'm using. What happened is that I had some power issues causing this system's power to be interrupted several times and basically an on/off on/off situation. The system won't boot, I just get a flashing cursor and no message or error from GRUB. Obviously the problem is that my MBR seems corrupt or some other issue. My........
  • 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........
  • SSH Slow Login even with SSHD UseDNS no parameter


    Icouldn't understand why on one system it took a few minutes to get the SSHlogin prompt when connecting to other systems. The other systems all had the UseDNS parameter set to no, which almost always resolves the login prompt delay. The reason is Ubuntu and perhaps Debian and other distributions /etc/nsswitch.conf file Edit yours to have the "hosts" line like so (notice that files and dns are the primary resolution choice........
  • SSH Server Slow/Lagged/Delayed Login Response


    This is really something the SSHServer developers should consider. The cause of this annoyance is because of failed DNS lookups on your IPaddress, which is especially common for many dedicated/col-located servers and also computers on internal NAT/private networks. The chances are this is the cause of your SSHSlow/Delayed Login problems. The easy solution to SSH Login Problems Edit /etc/ssh/sshd_config Add this line to disable r........
  • OCFS2 crash


    When trying to even cd or ls the mounted OCFS2 partition it crashes. Ithink 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........
  • SSH Problem User username from 127.0.0.1 not allowed because not listed in AllowUsers


    User username from 127.0.0.1 not allowed because not listed in AllowUsers What's going on? The user was created properly, it has been defined as having a shell entry and the entry for /etc/passwd and /etc/shadow is set just fine. This is a new and very smart/secure feature of SSHD. It is simple and yet effective, but also very annoying if you didn't know about it being implemented and that hand editing of /etc/ssh/sshd_config is required to allow a newly add........
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