When Is It Time to Leave Your VPS, VDS, and Dedicated Server Provider?
Choosing the right hosting solution—be it Virtu........
Welcome to our in-depth guide on configuring NVIDIA GPUs with Docker on Ubuntu. This post is tailored for developers, data scientists, and IT professionals who are looking to leverage the power of NVIDIA's GPU acceleration within Docker containers.
Whether you're working on machine lea........
The easiest way for the current running kernel is:
update-initramfs -u -k `uname -r`
You could change -k to a specific kernel name if for some reason the current is not running (eg. if you are chrooted or in recovery mode).
If you want to update all kernels then use "-k all"
update-initramfs -k all -u
update-initramfs: Generating /boot/initrd.img-5.4.0-162-generic........
Sometimes manual intervention on various Linux system's, including Debian, is required to fix things after waking up from sleep.
One persistent issue is the sound system / pulseaudio needing to be reset and not working until you do that after waking up. It's not clear if it's an OS issue itself or the sound driver, but this will fix things.
Where do we put scripts or commands that need to be used upon wakeup automatically?
/lib/systemd/syst........
Debian based OS's have a similar issue as the behavior in RHEL/CentOS dhclient, which is that if you have an interface that relies on DHCP, if the first attempt fails, it will quit and stop. This is a problem especially if you are using your Linux as a router or something else mission critical, but where the internet for some reason may have been down or the DHCP server it gets a lease from broken.
The expected behavior you would hope is that when things are back online that the........
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........
Here is the scenario, you are using QEMU/KVM and are using something like the AC97 sound driver to pass the host audio to the guest via pulseaudio. This is useful because you can transparently pass your mic input from the host which means you can mute your microphone from the host, which prevents the guest from receiving any mic input even if unmuted.
Mute / Unmute Fix
This issue also seems to happen even if you press the mute button on the microphone and then unmute,........
It is very silly but the default on the ifup-eth script tells dhclient ( the program that obtains a DHCP IPaddress if you have selected DHCPin your ifcfg-eth* config file) to EXIT / QUIT if the first attempt to obtain a lease fails.
No amount of dhclient.conf settings will fix this because if dhclient is started with -1 (which it is by default)then dhclient will quit.
This is obviously very bad for MOST cases. Say for example you have a power outage or........
#!/bin/bash
sshcommand="ssh -N -R 20000:localhost:22 user@8.8.8.8"
result=`ps aux|grep $sshcommand"|grep -v grep`
if [ -z "$result" ]; then
echo "we are going to connect"
$sshcommand
else
echo "we are already connected"
fi
This is a handy script you can use and then add it to cron.
Save........
I tried to stop a qemu-img copy or clone and it broke everything. It was fine to "stop" it from the GUI but a process still persisted so I killed the relevant qemu-img and the kernel went crazy. It also may not have helped that I tried to lvremove a different volume (an unused disk). But either way it breaks LVM (you cannot even run lvdisplay) so a reboot is necessary.
Jan 17 06:45:21 testserver kernel: [ 5680.439337] systemd-udevd D 0&nbs........
First you need the "iptables-persistent" package. This gives you an init script that loads your settings from /etc/iptables/rules.v4 and rules.v6
When you install it, it wll save your default setings in /etc/iptables.
sudo apt-get install iptables-persistent
Remember that the rules are stored here:
For IPV4: /etc/iptables/rules.v4
For IPV6: /etc/iptables/r........
mytop is one of my favorite tools and it is fairly simple aside from a few caveats and issues that persist to this day.
To install it on Centos:
yum -y install centos
Configure ~/.mytop
vi ~/.mytop
user=root
host=localhost
db=test
#port=3306
socket=/var/lib/mysql/mysql.sock
header=1
color=1
Try runni........
apt-get install pptp-linux
echo "yourvpnusername * yourpasspass *" >> /etc/ppp/chap-secrets
vi /etc/ppp/peers/provpnaccounts.com
enter (ignore the lines):
============
pty "pptp server.provpnaccounts.com --nolaunchpppd"
name testuser
#remotename PPTP
require-mppe-128
file /etc/ppp/options.pptp
==========........
[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........
This is the most I can get when plugging in a hard drive hot and only on some power connectors.
[71656.314271] ata5: exception Emask 0x50 SAct 0x0 SErr 0x90a02 action 0xe frozen
[71656.314277] ata5: irq_stat 0x00400000, PHY RDY changed
[71656.314285] ata5: SError: { RecovComm Persist HostInt PHYRdyChg 10B8B }
[71656.314294] ata5: hard resetting link
[71660.360686] ata5: softreset failed (device not ready)
[71660.360694] ata5: applying........
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 differentMAC, it assigns it one higher (eg. eth1).
See the example below, I have eth2 now so how doI fix it?........
Neither the blkid or the UUID internal to mdadm work to automount for some reason in Debian
partprobe doesn't work but was a good suggestion from: http://pato.dudits.net/2008/11/03/special-device-uuidxxxxxxxxxxxxxxxx-does-not-exist-especially-with-lvm
mount: special device /dev/disk/by-uuid/431b9b96-29e8f298-e89bd504-7065bddd does not exist
mdadm -D /dev/md_d12
mdadm: metadata format 00.90 unknown, ignored.
/dev/md_d12:
&nb........
I separated the 2 drives in the RAID 1 array.
1 is the old one /dev/sda and is out of date, while the separated other one /dev/sdc was in another drive and mounted and used with more data (updated).
I wonder how mdadm will handle this:
usb-storage: device scan complete
md: md127 stopped.
md: bind
md: md127: raid array is not clean -- starting background reconstruction
raid1: raid set md127 active with 1 out of 2 m........
Create New RAID 1 Array:
First setup your partitions (make sure they are exactly the same size)
In my example I have sda3 and sdb3 which are 500GB in size.
mdadm --create /dev/md2 --level=1 --raid-devices=2 /dev/sda3 /dev/sdb3
mdadm: array /dev/md2 started.
Check Status Of The Array
*Note I already have other arrays md0 and md1.
You can see below that md2 is syn........
Which one does the OS care about? blkid says the UUID is "787f1fa4-b010-4d77-a010-795b42884f56" while md insists its UUID is "4d96dd3b:deb5d555:7adb93cb:ce9182d9"
When in doubt, do we assume the OS takes the one from blkid?
/dev/md0: UUID="787f1fa4-b010-4d77-a010-795b42884f56" TYPE="ext3"
[root@localhost ~]# mdadm -D /dev/md0
/dev/md0:
Version : 0.90
&........
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........
mdadm --assemble --scan
mdadm: /dev/md/diaghost05102010:2 has been started with 2 drives.
mdadm: /dev/md/diaghost05102010:1 has been started with 2 drives.
mdadm: /dev/md/diaghost05102010:0 has been started with 2 drives.
-bash-3.1# cat /proc/mdstat
Personalities : [linear] [raid0] [raid1] [raid6] [raid5] [raid4] [multipath]
md125 : active raid1 sda1[0] sdb1[1]
14658185 blocks super 1.2........
Igot this after copying a VMWare image onto another machine in Debian.
SIOCSIFADDR No such device eth0 error while getting interface flags
The solution
1.) Find and edit the device line in persisent-net.rules note it will be prefixed with something like z25 or something else.
vi /etc/udev/rules.d/z25_persistent-net.rules
The easiest way is to comment anything out.
If you are feeling........