• How To Upgrade Debian 8,9,10 to Debian 12 Bookworm


    Step 1.) Upgrade to Debian 11 first The process to go to Debian 12 is not as smooth as 11, when trying to upgrade from Debian 10. In fact, it doesn't work directly, so you'll first need to follow this guide to update to Debian 11, reboot and come back here if successful. Step 2.) Update sources.list Update your /etc/apt/sources.list like this: deb http://........
  • How to use the FTDI USB serial cable to RJ45 adapter to connect to the console on Cisco/Juniper Switch Router Firewall in Linux Ubuntu Debian Redhat


    This should work for most console ports of other manufacturers too. It is a quick and simple method for emegencies or deploying a few appliances/devices in a non-standard environment or small environment. However, if this is a route thing, or the equipment is not physically close to you, it would be best to use some sort of "Terminal" server which is an IP connected switch with several serial ports built-in for this purpose. Normally they accessible by web/........
  • kernel panic initramfs not syncing cause solution


    Check your initramfs if it's missing /dev/null or /dev/console, this is likely the reason. If you want all actual devices to be created you could also enable devtmpfs in your kernel (.config) and mount like this during init: CONFIG_DEVTMPFS=y CONFIG_DEVTMPFS_MOUNT=y mount -t devtmpfs none /dev But note devtmpfs will not create /dev/null or /dev/console for........
  • Cisco 2900 3900 Router Password Reset How To Reset Enable Password


    It is a bit different and annoying here for these types of routers/models as you need to physically remove the CF (Compact Flash) and only then, will it enter ROMMON mode (Ctrl + Pause remotely over the console will not do it for us). This means you cannot do this remotely, or at least not without the help of a remote/physical helper. Step 1.) Power off, router and remove CF Disk Slot#2 Go to the router and remove the slot#2 cover uses your hand or it may help to use a........
  • Error opening tftp://10.0.2.2/network-confg (Permission denied) - How To Fix Cisco Router Switch Error Solution Console


    How To Fix This Cisco Switch/Router Error %Error opening tftp %Error opening tftp://10.0.2.2/network-confg (Permission denied) %Error opening tftp://10.0.2.2/cisconet.cfg (Permission denied) %Error opening tftp://10.0.2.2/router-confg (Permission denied) %Error opening tftp://10.0.2.2/ciscortr.cfg (Permission denied) %Error opening tftp://10.0.2.2/network-confg (Perm........
  • i915 nouveau Nvidia GPU not starting lightdm Xorg failing solution for Could not determine valid watermarks for inherited state


    It may appear to be an Xorg or lightdm/gdm/mdm error but in reality for many users with this issue, it's a driver conflict and issue. I had a system that had two GPUs, an Intel and Nvidia GPU. The only thing that got it working was to remove the nouveau driver and blacklist it so it never came back, then the Intel GPU works fine without these issues. Solution sudo rmmod nouveau add nouveau/other driver to blacklist edit th........
  • Docker Tutorial HowTo Install Docker, Use and Create Docker Container Images Clustering Swarm Mode Monitoring Service Hosting Provider


    The Best Docker Tutorial for Beginners We quickly explain the basic Docker concepts and show you how to do the most common tasks from starting your first container, to making custom images, a Docker Swarm Cluster Tutorial, docker compose and Docker buildfiles.........
  • Cisco Howto Configure Console Port/Terminal/Comm Server with Async Cable Setup


    This assumes that you've already installed the relevant HWIC cards eg. Cisco Asynchronous Serial NIM These are essentially cards that you install into your router, once installed you connect an Async cable to one of the ports on the card which normally gives you 8 console cables and are normally labelled 1 through 8. You connect all of the cables to the devices you need (even non-Cisco devices) whether switches, routers or firewalls, they will usually work. The real m........
  • Cisco Switch Howto Reset Password


    This was done on a 2900 but applies to all the switches of the same era. Step 1 - Power Cycle and enter recovery mode If you have physical access you can power cycle and hold the mode button down for 15 seconds. After that the SYS light will flash on the switch and you will see the following screenshot. If you don't have physical access (eg. it is a datacenter swich over console only) then power cycle and hit "Ctrl+Pause/B........
  • Cisco Router Password Reset Howto Guide Solution Cannot Login /Unknown Enable Password 2600, 2800, 2900, 3900


    It is common that you may get access to undocumented equipment and need to reset the password. This applies to many Cisco routers whether 2600, 2900, 3900 etc... Cisco's Guide says to hit Ctrl +Pause/Break but if it doesn't work on some devices causing people to say "cisco password reset pause break does not work", you can see Cisco's alternative key combinations here:........
  • Linux Grub not booting the intended kernel solution in Debian, Mint, Ubuntu how to specify which kernel to boot by default


    Traditionally kernels were numbered starting from 0 but by default the "new style" of grub boot loading considers each subkernel item to be different so if you have 3 entries for 4.40-148 rather than counting for 1. To get the expected behavior let's show this example and how we can boot it We do a grep on menuentry in /boot/grub/grub.cfg to see all of the bootable kernels rather than scrolling through loads of extra entries we don't care about (thou........
  • dynagen / dynamips 100% high CPU usage solution - how to set the idlepc value


    The idlepc value is very important to dynamips and it is both image and often CPU dependent. There is no "magic"value that will work for all images and all CPUs so this is why I'll show you a quick and handy way. Also don't be disappointed, some values do not work well but idlepc gives you several. For example in my example below #6 didn't help at all but #7 got me down to about 6% CPU from 99-100%. *Befo........
  • How To Setup a Cisco CME (Cisco Manager Express) Virtual Router under Linux using dynamips and dynagen


    This tutorial will get your router up and running using emulation tools. In this case we'll be getting a Cisco C7206 (C7200 series) VXR router going which also supports SCCP VOIP services. dynamips is the emulator itself and dynagen is the front-end tool that helps us control everything. It is used by tools such as gns3 and eve-ng. Together the two tools (dynamips and dynagen) allow us to create and emulate REAL router........
  • Linux How To Change NIC Name to eth0 instead of enps33 or enp0s25


    Most newer distros inexplicably cause your NIC to have what Icall "random" non-standard name conventions because of systemd. This is a big problem for many people and especially those running servers. Imagine that you have a static IPconfigured for ens33 but then the hard disk is moved to a newer system, the NIC could be anything from ens33 to enp0s1, meaning that manual intervention is required to go and update the NIC config file (eg. /etc/network/interfa........
  • Radeon R3 GPU on Debian Crashing


    Occasionally my whole screen locks up and I cannot even swith to the console and I find this in my syslog: *-display description: VGA compatible controller product: Mullins [Radeon R3 Graphics] vendor: Advanced Micro Devices, Inc. [AMD/ATI]  ........
  • Linux Console Login Screen TTY Change Message


    This is all controlled by /etc/issue You can basically enter anything in there that you like, but there are preset variables that are mentioned at the end of the page that discuss this. Some examples of /etc/issue: Centos 7: S Kernel r on an m Ubuntu 16.04: Ubuntu 16.04.6 LTS n l You can also insert any of t........
  • Linux Over VNC VMWare How To Switch Virtual Terminals Console Without Using Ctrl+Alt+F1


    This is a common issue that I haven't seen many answers for on the internet. When you are using Linux as your host machine and you are connecting to another Linux machine over VNC you CANNOT use Ctrl+Alt+F1 to change virtual consoles as it sends the keys to your actual local machine. In many versions of Linux you can cycle through virtual terminals including over VNC using this: Alt + Left Arrow or Alt + Right Arrow This........
  • Cisco Switches How To Get Of Port Line Status Console Messages


    00:55:07: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to down 00:55:09: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up Switch(config)#no logging console ........
  • Cisco Switch Setup Guide Command List


    Enter configuration console: enable configure terminal This is important because if your console doesn't look like below none of the commands will work! Switch(config)# Save and Apply Settings wr Show Switch Configuration: show run Show Port List/Sta........
  • Cisco Switch Reset To Factory Defaults


    This works on the 2000 and 3000 series generally. *The easy way is to just hold the mode button for 10+ seconds. The full/proper way is below: 1.) Either power on the unit and hold the "mode" button or hold the "mode" button until you see the below: 00:04:08: %SYS-7-NV_BLOCK_INIT: Initalized the geometry of nvram 00:04:08: %EXPRESS_SETUP-6-CONFIG_IS_RESET: The configur........
  • 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........
  • Supermicro IPMI / KVM / BMC Remote Console Screen Resizing Issue - Window Cut Off Solution


    It could just be my specific Java but other KVM/IP works ok on my machine but with Supermicro's IPMI for some reason the console window doesn't resize and even putting it in full screen leaves the window cut off as shown below: As you can see above the screen is cut off you can't see the "Iagree" on the right side. The window resi........
  • Linux Mint 18 Screen Goes Dark or Black After Screensaver or even when using the Desktop Solution


    You can search for this bug and it seems like it may be related to ecryptfs and is many years old. The symptoms are that you return to the computer and the screensaver was active or the screen was asleep/black and it doesn't seem to come back. But you check by SSH the computer is running fine and are frustrated you'll lose your running programs and have to reboot. There is a simple solution: Ctrl + Alt + F1 Ctrl +Alt + F8 Ba........
  • 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 Ubuntu Mint Debian cannot play xvid,x264,mp4 or any videos codec issue - xplayer Could not initialize supporting library.


    In xplayer Iget the following error "Could not initialize supporting library.". It actually looks more like a gstreamer issue. For those wondering what the default video player is called it is "xvid" and not "totem" anymore like previous versions. Basically it looks like some codecs are missing when I uninstalled another program it uninstalled other programs and codecs that it shouldn't have. I've tried installing all the gstre........
  • wget howto output to terminal or script instead of file


    wget -qO You just need the -qO switch and you'll be good to go, the output then goes to your console/screen/script rather than a file.........
  • 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:........
  • 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........
  • Openshot 2.2 is very unstable always crashing in Linux Mint 18.1!


    Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Missing folder chosen by user: Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Removed missing file: MAH02949.MP4 Jun 1 15:45:57 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: ui_util:WARNING Icon theme media-playback-start not found. Will use backup........
  • text to speech for Linux


    espeak - is horrible and sounds very old and robotic echo "hello there"|espeak #don't know how to use mbrola and plugins cicero jovie just seems to be a graphical interface to espeak There is also sbreader/sapi Google's Text To Speech Works Quite Well #!/bin/bash say() { local IFS=+;/usr/bin/mplayer -ao alsa -really-quiet -noconsolec........
  • Centos cannot login by console or ssh session closed immediately


    In my case I could login with the initial install but I rsync'd everything over while preserving ownership and permissions to another RAID partition and booted from that.was fine before. The problem is that you are kicked out the second you login and the problem was SELINUX for some reason (perhaps it noticed something strange when it was moved to the new partition) login: pam_unix(login:session): session opened for user root by LOGIN(uid=0) login: ROOT LOG........
  • Centos/obfsproxy errors


    I never did get it working, it is too bad as obfsproxy should really be an option and integrated into the OpenVPN client and server or something similar: yum -y install python-pip python-devel No package python-pip available. #install the EPEL repo python-pip install obfsproxy python-pip install obfsproxy -bash: python-pip: command not found pip install obfsproxy &........
  • mysql how to kill individual process/query


    Enter the console as root mysql -u root -p Then kill the process (where 1234 = the thread ID) kill 1234 It's also a good idea to use a tool like "mtop" to monitor which processes and queries are slow, killing them is a temporary fix while you try to isolate the actual problem.........
  • Linux Centos 6 Weird Kernel Panic


    Kernel panic - not syncing: Attempted to kill init! Pid: 1, comm: init Not tained: 3.2.51-3.el6.x86_64 #1 Call Trace: panic+0x8c/0x1a2 forget_original_parent+0x34d/0x360 exit_notify+0x12/0x140 do_exit+0x1d8/0x400 do_group_exit_+0x50/0xc0 sys_exit_group+0x12/0x20 system_call_fastpath+0x16/0x1b panic occurred, switching back to text console........
  • 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........
  • Asterisk DOS attack - failed for '173.242.117.192' - Peer is not supposed to register [May 23 15:46:07] ERROR[32748]: chan_sip.c:13158 register_verify: Peer '153' is trying to register, but not configured as host=dynamic


    This happened to a customer Asterisk server and it somehow found the ID of the registration account to the upstream SIP server and was railing connection attempts (it filled up the console and there were literally thousands per second). Basically this caused all incoming and outgoing calls to fail. It was a temporary fix but the solution was to block that specific IP, it's hard to stop it 100% because the customer needs the default SIP port.........
  • 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........
  • Kernel panic - not syncing: Attempted to kill init! Pid: 1,comm: init Tained: G I------------- 2.6.32-358.el6.x86_64 #1 Call Trace: [] ? panic+0xa0/0x16f [] ? do_exit+0x862/0x870 [] ? fput+0x25/0


    Kernel panic - not syncing: Attempted to kill init! Pid: 1,comm: init Tained: G I------------- 2.6.32-358.el6.x86_64 #1 Call Trace: [] ? panic+0xa0/0x16f [] ? do_exit+0x862/0x870 [] ? fput+0x25/0x30 [] ? do_group_exit+0x58/0xd0 [] ? sys_exit_........
  • kvm cannot boot xen guest using lvm


    This booting error is because the Xen PV guest image uses the Xen kernel, this is not compatible with anything but a host running a Xen kernel. I did a kpartx -av virtual.img and then it created some partitions that showed up in fdisk. I mounted it and did a chroot into it and removed the xen kernel and installed a normal kernel but Xen still shows the same kernel in Grub (only the Xen one). This is strange but it seems like this Xen PV guest has some sort of hidden or........
  • 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........
  • how to exit xen console session from xm


    It sure is annoying when you connect to the console using xm and it locks your shell session. It doesn't really, you just need to know it is "Ctrl + ]" to exit it. Once again to exit an xm console session, press Ctrl + ]........
  • 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........
  • Santrex Review Scam Complaint - Stole My Money Fraud


    Santrex Review/Scam/Complaint Santrex never provided any working server, I believe it was just a dummy management Solus server because the server said it was booted but never connected to the console. I complained to them and eventually the support admitted the server was not working and to wait for 24 hours. I waited for 4-days, after which they sent an e-mail saying my service was being disabled for SPAM ...(when SolusVM shows 0kb of traffic). Th........
  • VPS Server Scam/Review/Complaint List


    These are the only two I've encountered but here is the low-end and note my story is not at all unique. In my case I was scammed out of money and did not receive any service at all from either company. Santrex Review/Scam/Complaint Santrex never provided any working server, I believe it was just a dummy management Solus server because the server said it was booted but never connected to the console. I complained to them and eventually the support adm........
  • NotifyByPopup::slotDBusNotificationClosed: 465 -> 0 knotify(31135) NotifyByPopup::slotDBusNotificationClosed: failed to find knotify id for dbus_id 465


    I keep getting this in my SSH/Bash console: NotifyByPopup::slotDBusNotificationClosed: 465 -> 0  ........
  • Use rcconf to edit startup/init.d/init scripts on Debian/Ubuntu based distributions


    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........
  • rsync skipping non-regular file


    skipping non-regular file "mnt/lib/udev/devices/console" skipping non-regular file "mnt/lib/udev/devices/kmem" skipping non-regular file "mnt/lib/udev/devices/loop0" skipping non-regular file "mnt/lib/udev/devices/null" skipping non-regular file "mnt/lib/udev/devices/ppp" skipping non-regular file "mnt/lib/udev/devices/net/tu Solution for skipping non-regular file You need the -D........
  • Picking an FTPD (vsftpd) Server in Linux Centos/Debian


    I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find. yum search ftp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * rpmforge: ftp-stud.fht-esslingen.de * base: mirrors.netdna.com * updates: updates.interworx.info * addons: yum.singlehop.com * extras: mirrors.netdna.com rpmforge........
  • Basic Port Listing


    Basic Port ListingHopefully someone finds this useful or at least interesting. http://www.sans.org/top20/#u9 Name Port Protocol Description Small services ........
  • Debian/Ubuntu/Kubuntu Bash/Console/Terminal/Putty Home and End Keys Don't Work or Produce a ~


    This is a very weird, annoying and bizarre quirk with many distributions, especially Debian. The home and end keys don't work, but it's a simple fix as long as you found this article :) You just have to edit /etc/inputrc: Find the commented lines as shown below: # "e[1~": beginning-of-line # "e[4~": end-of-line *If you can't find the above, just copy and paste the code below into your inputrc, it will en........
  • Configuring OCFS2 Clustered File System on Debian Based Linux including Ubuntu and Kubuntu


    There's a lot of information and guides on OCFS2 for RHELand 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........
  • Latest Articles

  • How high can a Xeon CPU get?
  • bash fix PATH environment variable "command not found" solution
  • Ubuntu Linux Mint Debian Redhat Youtube Cannot Play HD or 4K videos, dropped frames or high CPU usage with Nvidia or AMD Driver
  • hostapd example configuration for high speed AC on 5GHz using WPA2
  • hostapd how to enable and use WPS to connect wireless devices like printers
  • Dell Server Workstation iDRAC Dead after Firmware Update Solution R720, R320, R730
  • Cloned VM/Server/Computer in Linux won't boot and goes to initramfs busybox Solution
  • How To Add Windows 7 8 10 11 to GRUB Boot List Dual Booting
  • How to configure OpenDKIM on Linux with Postfix and setup bind zonefile
  • Debian Ubuntu 10/11/12 Linux how to get tftpd-hpa server setup tutorial
  • efibootmgr: option requires an argument -- 'd' efibootmgr version 15 grub-install.real: error: efibootmgr failed to register the boot entry: Operation not permitted.
  • Apache Error Won't start SSL Cert Issue Solution Unable to configure verify locations for client authentication SSL Library Error: 151441510 error:0906D066:PEM routines:PEM_read_bio:bad end line SSL Library Error: 185090057 error:0B084009:x509 certif
  • Linux Debian Mint Ubuntu Bridge br0 gets random IP
  • redis requirements
  • How to kill a docker swarm
  • docker swarm silly issues
  • isc-dhcp-server dhcpd how to get longer lease
  • nvidia cannot resume from sleep Comm: nvidia-sleep.sh Tainted: Linux Ubuntu Mint Debian
  • zfs and LUKS how to recover in Linux
  • [error] (28)No space left on device: Cannot create SSLMutex Apache Solution Linux CentOS Ubuntu Debian Mint