• efibootmgr: option requires an argument -- 'd' efibootmgr version 15 grub-install.real: error: efibootmgr failed to register the boot entry: Operation not permitted.


    This sometimes happens when trying to install the EFIversion of grub to a device when you are booted into Legacy/MBR mode. It doesn't seem to occur on all machines, but some and seems somewhat BIOS dependent. grub-install --target=x86_64-efi /dev/sda Installing for x86_64-efi platform. grub-install.real: warning: Couldn't find physical volume `(null)'. Some modules may be missing from core image.. grub-install.real: warning: Couldn't find physica........
  • LightDM Mint Ubuntu Debian won't start errors Nvidia Graphics


    This error implies that there may be an issue with Xorg or maybe your NVIDIA GPU cannot start or initialize: 35 laptop kernel: [ 2031.857704] nvidia: loading out-of-tree module taints kernel. 35 laptop kernel: [ 2031.857724] nvidia: module license 'NVIDIA' taints kernel. 35 laptop kernel: [ 2031.857725] Disabling lock debugging due to kernel taint 35 laptop kernel: [ 2031.873280] nvidia: module verification failed: signature a........
  • GlusterFS HowTo Tutorial For Distributed Storage in Docker, Kubernetes, LXC, KVM, Proxmox


    This can be used on almost anything, since Gluster is a userspace tool, based on FUSE. This means that all Gluster appears as to any application is just a directory. Applications don't need specific support for Gluster, so long as you can tell the application to use a certain directory for storage. One application can be for redundant and scaled storage, including for within Docker and Kubernetes, LXC, Proxmox, OpenStack, etc or just your image/web/video files or even da........
  • How To Create OpenVPN Server for Secure Remote Corporate Access in Linux Debian/Mint/Ubuntu with client public key authentication


    Why choose OpenVPN instead of a firewall appliance? OpenVPN can be a reliable and easy replacement for traditional hardware or just be an additional tool that your company uses so that the firewall can focus on its job rather than acting as a VPNappliance at the same time. When comparing OpenVPN with traditional firewal........
  • tag#4 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE tag#4 Sense Key : Illegal Request [current] res 40/00:b4:98:02:00/00:00:00:00:00/40 Emask 0x10 (ATA bus error) solution


    You might assume you have a bad drive or the SATA interface/cable is bad, or the power supply is bad/weak to the drive. These are all possible issues, but definitely check your SATA cable for "twisting". It is a big issue because until the error stops or times out, your system will not boot (in my case this was the case even though the drive with the issue was not part of the OS or booting process at all). If you run an open rig that you move around often that ha........
  • Huion and Wacom Tablets How To Install in Linux Mint / Ubuntu and make the stylus work properly


    It took a lot of fiddling to make a Huion Kamvas 13 Pro work in Linux but it simple once you know what to do. Don't bother searching as it is unlkely there is a guide out there that will actually make your tablet work. It mainly comes down to the fact that the hid_uclogic kernel module is buggy or doesn't support MANYof these wacom based/Huion tablets properly. What was happening with me is that Ihad the Kamvas 13 Huion setup as a secondary screen/monitor.&nb........
  • How To Get Started on Ubuntu with gpt-2 OpenAI Text Prediction


    apt install software-properties-common add-apt-repository ppa:deadsnakes/ppa apt update apt install python3-pip apt install python3.7 curl gnupg python3.7-dev git ln -s /usr/bin/python3.7 /usr/bin/python3 pip3 install numpy keras_preprocessing curl https://bazel.build/bazel-release.pub.gpg | sudo apt-key add - echo "deb [arch=amd64] http://storage.googleapis.com/bazel-apt stable jdk1.8" | sudo tee /etc/apt/sources.list.d/bazel........
  • How To Install python 3.4 3.5 and up on Linux with wine - Working Solution


    This is sure simple if you follow the guide but it took a lot of hacking around to make this work on Debian/Ubuntu! Now before you ask why bother running wine and python, the reason is because Python executables are NOT cross-platform. If you run pyinstaller in Linux, that binary will only run on Linux and the same if you do it in Windows. So it is preferable if you have a single environment that you can create Linux and Windows binaries from rather than running 2 separate........
  • ssh Received disconnect from port 22:2: Too many authentication failures


    If you are getting this error it is usually caused by having more than 5 keys in your ".ssh" directory. It is a bit of a bug and this is how it manifests itself. You will find at this point that you are not given any chance to enter a password, or if you are using key based auth that the same thing happens. You'll also find that this is happening with ALLservers you try connecting to. The solution is to move away key pairs from .ssh so that there ar........
  • Convert and install to LUKS Encrypted Drive Ubuntu 18.04 19.10 Linux Mint and Debian Based Linux


    The reason for doing this is that the installer doesn't seem to work properly for LUKS and the server installer doesn't even support LUKS anymore. When you use the GUI install on Desktop for LUKS it won't boot and will just hang after you enter your password. So the only reliable way is to do it ourselves. 1.) Make a default minimal install of Ubuntu 2.) Have a secondary disk on the server or VM. 3.)........
  • ADATA USB Thumb Drive Issues


    This is the reason that I don't like the new ADATA USB drives such as the UV128/64GB or 128GB drives and other ones that look to be the same style (the green sliding USB connector). They just don't work well from new and never work properly at any point. [ 788.242463] usb 1-1.2: new high-speed USB device number 16 using ehci-pci [ 788.339816] usb 1-1.2: New USB device found, idVendor=125f, idProduct=db8a [ 7........
  • tftp Linux xinetd verbose logging


    It is much more useful to have meaningful and detailed logging from tftp to see what is or isn't happening especially for VOIPand other embedded device appications: Edit the file: vi /etc/xinetd.d/tftp Change the server line like this: server_args = -s /var/lib/tftpboot........
  • SSH error cannot Forward or Listen "bind: Cannot assign requested address"


    debug1: Local connections to LOCALHOST:18006 forwarded to remote address 192.168.1.93:8006 debug1: Local forwarding listening on 127.0.0.1 port 18006. debug1: channel 0: new [port listener] debug1: Local forwarding listening on ::1 port 18006. bind: Cannot assign requested address What we are seeing is that we can't listen on an IPV6 address of ::1. We need to tell SSH to stop using IPV6 so we'll edit ssh_config to take care of this issue........
  • Why SMART is not smart at all and doesn't properly predict disk errors that cause a kernel panic or crash


    Before getting into the output here is my typical experience with SMART, there is what I call a "bad disk" with pending and uncorrectable sectors that cannot be reallocated. It has caused a kernel panic and system crash repeatedly as we can see from the logs. But SMART says it has "PASSED" its self assessment. SMART is still useful to me but it is more about looking at Current_Pending_Sector. Any time I have had anything but 0 for that attribute it........
  • VMWare Vsphere VCSA Graphical Install Creates json


    yes it does create its own json ============================================ cat /tmp/vcsaUiInstaller/ovftool-20180809-175238948-20180809-175603497.log |grep -i json 2018-08-09T17:56:04.238-07:00 verbose OVFTool[30966] [Originator@6876 sub=Default] Manifest file entry: SHA1(VMware-vCenter-Server-Appliance-6.7.0.12000-8832884_OVF10-file1.json) = 1deb658c724767697587d5909c4051c01813e6a1 --> ........
  • 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........
  • postfix errors fatal: no SASL authentication mechanisms /usr/libexec/postfix/smtpd: bad command startup -- throttling solution


    Jul 3 22:12:17mailserver postfix/smtpd[6195]: fatal: no SASL authentication mechanisms Jul 3 22:12:18mailserver postfix/master[4881]: warning: process /usr/libexec/postfix/smtpd pid 6195 exit status 1 Jul 3 22:12:18mailserver postfix/master[4881]: warning: /usr/libexec/postfix/smtpd: bad command startup -- throttling This only ever happens in my experience when the authentication method is actually Dovecot. Usually the problem........
  • /usr/bin/ld: cannot find -lboost_system-mt-s /usr/bin/ld: cannot find -lboost_filesystem-mt-s /usr/bin/ld: cannot find -lboost_program_options-mt-s /usr/bin/ld: cannot find -lboost_thread-mt-s collect2: error: ld returned 1 exit status make: *** [cag


    cagecoin linux compile: sudo apt-get install qt4-qmake libqt4-dev build-essential libboost-dev libboost-system-dev libboost-filesystem-dev libboost-program-options-dev libboost-thread-dev libssl-dev libdb++-dev libminiupnpc-dev Solution: sed -i s/"BOOST_LIB_SUFFIX=-mt-s"/"#BOOST_LIB_SU........
  • USB Device/MP3 Player not working properly and can't browse the device filesystem? Check the cable twice and again!


    Here is a simple MP3 player and now there's a reason to understand why the supplied cable has some kind of capacitor and is very short. These devices can be VERY finicky and any voltage fluctuation or difference is enough to cause issues. Take for example the error messages from Linux Mint: [804829.895414] usb 1-1: USB disconnect, device number 11 [806961.109030] usb 1-1: new high-speed USB device number 12 using xhci_hcd........
  • Linux shows my drive as being dead is it really? Buffer I/O error on device sdb, logical block 0 sd 3:0:0:0: [sdb] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00


    Normally the below would indicate a failing or failed drive. In this case the SATA port was unplugged and sometimes the Linux kernel/motherboard even with AHCIjust don't play nice and can't handle it. What happened is Iplugged in a new drive after removing another one. However the log shows that after the old drive was plugged in the Linux kernel kept complaining thinking the drive was there but not responding properly. This continued even with reseating........
  • What happens when you unplug 1 or more devices from an mdadm RAID array to simulate a failure in Linux Ubuntu/Centos/Debian?


    In short the two drives in the array were /dev/sdd and /dev/sde. The kernel sees they were unplugged and have gone down as you can see below. mdadm caught the first one being unplugged /dev/sde and disabled the missing drive. However when the final drive that was part of the array is unplugged it didn't notice at all. Instead it complains about an IO error later for drives that the kernel knows do not exist anymore. [45817.162728] ata4: exception........
  • mdadm and lvm how to completely disable and remove vg/pv/lv


    In short the solution is just to use vgremove for the actual /dev/mapper device: vgremove /dev/mapper/backups-backuplv box mnt # mdadm --manage /dev/md8 --stop mdadm: Cannot get exclusive access to /dev/md8:Perhaps a running process, mounted filesystem or active volume group? box mnt # lv lvchange lvconvert lvcreate l........
  • 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 ........
  • 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........
  • Brand new WDD 500GB Blue 3.5 SATA Drive Dead After Shipping


    These drives seem to die very easily during shipping: sd 0:0:0:0: [sda] Unhandled error code sd 0:0:0:0: [sda] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK sd 0:0:0:0: [sda] CDB: Read(10): 28 00 18 8b 65 e0 00 00 08 00 end_request: I/O error, dev sda, sector 411788768 sd 0:0:0:0: [sda] Unhandled error code sd 0:0:0:0: [sda] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK sd 0:0:0:0: [sda] CDB: Read(10): 28 00 18 8b........
  • 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:........
  • 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 Burn ISO Image using cdrtools/dvdrtools for Linux/Unix Ubuntu/Debian/RHEL/Centos etc..


    It really is as simple as: cdrecord -v dev=/dev/sr0 pathtoyourisoimage.iso -v is for verbose, I prefer it but if you don't you won't see as much output like below (I like to know the details and exactly what's happening) dev=/dev/sr0 specifies the device name of your burner (they say not to use it and to specify some weird annoying device string but using the raw /dev has always worked for me and is how it should have been implemented from the start IMHO)........
  • htaccess modrewrite problem with rewriting url with- dashes solution


    I was getting frustrated with trying to write a simple URL like this: /example-withdash I used the htaccess code like this: Rewriterule ^example-withdash$ / [R=301] I also tried escaping the dash which I thought should have treated it as a literal but that didn't work either: Rewriterule ^example-withdash$ / [R=301] But it wouldn't work, apparently the "-" dash means don't substitute,........
  • Dying Samsung DVDRW Drive


    My Samsung drive failed on me, at first I thought it was the enclosure but a direct SATA connection causes the same problems for discs that are inserted. It will work fine for a few minutes but then starts spewing the errors below. I've never been a fan of Korean made optical drives and have always had trouble with them. The problem is that I don't believe NEC and Lite-ON make drives anymore, and I considered them the leaders. Apr 7 11:58:48 bo........
  • 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 (althoughI 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........
  • LUKS/cryptsetup Tutorial for Linux Hard Drive Partition Encryption


    This is based on Debian Linux but should apply equally to any *nix distro. Install LUKS/crypt-setup apt-get install cryptsetup Setup your LUKS Partition Of course change /dev/md2 with whatever partition you intend to use LUKS on. cryptsetup --verbose --verify-passphrase luksFormat /dev/md2 You'll be asked to verify your decryption password twice *DO NOT FORGET THIS PASSWORD AS IT IS NOT RECOVERABLE!........
  • 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........
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