If you have ever seen a system where terminal in the GUI closes instantly and/or you cannot SSH to the server/machine.
mount -t devtmpfs none /dev
mount -t devpts none /dev/pts........
Have you ever tried mounting a partition that you exists but you get this error?
mount: /mnt: can't read superblock on /dev/sda1.
The superblock in this example was bad because the physical disk had corruption and bad blocks/sectors. However, the data was generally accessible and you can always try this trick below (with caution and no warranty).
This is specifically for filesystems that place superblocks in multiple locations, which........
PTY allocation request failed on channel 0
You may have messed up your environment and specifically under /dev you may have remounted a wrong source point or otherwise killed /dev/pts
The solution is to recreate /dev/pts or fix whatever caused it to be wiped out or broken.
In verbose mode the client may show this:
#verbose client
Authenticated to 172.16.17.2 ([172.16.17.2]:22).
debug........
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://........
Let's say you have a directory /mnt/raid which has files and directories inside it, but nothing is mounted to it.
Then you mount a block device such as /dev/sdh to /mnt/raid
Even though /mnt/raid has files and directories there, you can only see the mounted contents of /mnt/raid.
How do we access the original contents?
Just do a bind mount of the root filesystem to another location.
mkdir /bindmount
mount --bind / /b........
Just in case, it is reocmmended to backup the original contents of the directory (especially your home dir) before proceeding.
Setup ecryptfs
Run this command: ecryptfs-setup-private
It will ask you for your login password, this is so that when you login, everything is automatically decrypted by using a passphrase that is wrapped with your login.
You can hit enter and leave things blank for an autogenerated passphrase (for mounting) or you can en........
In a lot of distros like Debian, ecryptfs will mount itself in /home/yourusername/Private
This is controlled by Private.mnt which may contain the mount path like this:
/home/yourusername/Private
Change the default mount location of ecryptfs by modifying this file:
home/.ecryptfs/yourusername/.ecryptfs/Private.mnt
After you unmount and relogin, you should find ecryptfs is now mo........
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........
In this example we install debian 10 with --variant=minbase which gives us a minimal/tiny install. Don't use variant if you want the full size install.
mkdir /tmp/deb10files
debootstrap --variant=minbase buster /tmp/deb10files/
Did you get an error?
debootstrap --variant=minbase buster /home/theuser/VMs/deb10files/
You'll get this error if you make a directory in your home........
1.) Create your EFI/ESP Partition
If you happen to have some free space on the drive already then this is easy, just create a new partition of at least 100M.
The nice thing about the EFI spec is that it must just be in the first 2.2TB of space so for most users, it means you can simply resize the last partition(downsize it by 100M) and then add an EFI partition at the end.
For example if you had this partition scheme:
/dev/sda1 = /........
I've seen this bizarrely happen on a newly partitioned and custom installed Linux install, particularly if you did not properly unmount before rebooting.
You can find reports of it happening on various
How to fix the error: invalid arch-independent ELF magic.
You need to boot into Live/Rescue mode, chroot into your OS properly and then do a grub-install on each drive that nee........
If you are doing a custom deployment and image, make sure that when you rsync'd or tar'd that you didn't mess up the symlnk of /etc/mtab to /proc/self/mounts
ln --force -s /proc/self/mounts /etc/mtab
Will fix this........
In this scenario, let's say you want to clone your OS at the filesystem level and the source system (the system you want to clone from) is in use.
Doing a blind rsync / is a big problem because it uses twice as much space for no reason.
The reason for this is that with ecryptfs you have a /home/.ecryptfs directory which has the actual encrypted versions of your files and folders. However your home directory (eg. /home/someuser) is mounted.
Doing the blind rsync will ca........
I've encountered this after upgrading some Debian/Ubuntu/Mint based systems for no explicable reason, although there are some bug trackers on Ubuntu that document this: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1889509
The short end of the solution is that you need to properly reinstall grub.
1.) Boot from a LiveCD
2.) Mount your root / filesystem and don't forget to mo........
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........
This may be necessary if you have a VM or if for some reason you just want to be more efficient with your space and have the flexibility of changing your swap space at will.
What we mean is the ability to use a "swap file" or similar to the Windows "pagefile" that normally resides on the root or c: partition of Windows.
Here's all you have to do and then you to can have a single partiton with everything, including the swap file on the root partition if you........
This happens during an apt update and is related to an issue with sources.list, which is particularly troubling, if you are doing a "live-build".
P: Configuring file /etc/apt/sources.list
Hit:1 http://deb.debian.org/debian bullseye InRelease
Get:2 http://deb.debian.org/debian bullseye-updates InRelease [39.4 kB........
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.........
This was done on Mint 20 but works the same on nearly any new Linux, but is only recommended for people comfortable or familiar with Linux. This method will work on almost all versions of Windows from NT, 2000, 2003 Server, 2008 Server, 2012 Server, 2016 Server, 2019 Server, 2022 Server, XP, Vista, 7, 8, 10 and 11.
However, if you want the easiest solution to........
So you're trying to browse to a properly configured Samba share but you get this error:
Unable to mount location
Failed to retrieve share list from server: Connection timed out
If your config is right, it can be due to a protocol miss-match where your client has not enabled SMB3 but by default the other side (server) has enabled it.
You can test this out to see with the smbclient tool........
Usually if you get the grub boot loader and it doesn't show any boot options, it's because grub was not installed correctly and/or the partition that it is supposed to be on has changed or does not exist. It can also happen if you install Linux to one drive, but the boot loader to another by accident, whether EFI or MBR/Legacy mode.
You can normally fix your booting/bootloader/MBR/EFI it by chrooting into your root partition:
#become root
sudo su........
Enable "cli" mode equivalent in JunOS
cli
Configure Mode
configure
So rather than going to the console on a Cisco switch and typing "enable" and then "conf t", the equivalent in JunOS is "cli" and "configure".
How Do You Apply Changes You've Made?
You can make all kinds of changes to the switch, but remember they are not........
The problem seems to be that whatever kernel and initrd you have is tied to an old version of CentOS 7 that is no longer in the current repos of most mirrors.
If you were previously able to PXEboot and install CentOS and you are sure your network and tftp are good the problem is that you have an outdated kernel and initramfs that point to a defunct version.........
$ ./test.sh
bash: ./test.sh: Permission denied
This happens normally because you are on a partition that was mounted as "user" and without the exec option. Also be sure to add exec at the end so no other options set noexec.
Change your fstab or add exec to your mount options:
/dev/md127 /mnt/md127 ext4 auto,nofail,noatime,rw,user,exec 0 0
........
When you automount a drive in /etc/fstab even if it's not important like an external drive that you only use sometimes and is not required for booting, it will prevent a successfuly boot.
If you disable quiet mode for booting you will see something like below "A start job is running for dev-disk ...."
How do we fix an fstab entry from preventi........
-?????????? ? ? ? ? ? shadow
----------. 1 root root 748 Jul 10 04:35 shadow-
cat: shadow: Input/output error
If you see this you are probably in big trouble, it could be a physical error or if it's a VM image that it is corrupted due to a physical error on the underlying disk/array/NAS or it could a........
chroot /root/kvmguests/4591915/mount
FATAL: kernel too old
This happens for example if you are in Centos 6 and trying to chroot into a system based on a newer kernel like 4.x+
You'll have to use a newer OS/kernel system to chroot into the environment or a VM running a newer kernel.........
It is unfortunate that LXC's dir mode is completely insecure and allows way too much information from the host to be seen. I wonder if there will eventually be a way to break into the host filesystem or other container's storage?
OpenVZ better security:
[root@ev ~]# cat /proc/mdstat
cat: /proc/mdstat: No such file or directory
/dev/simfs 843G 740G 61G........
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.)........
The cool thing here is that we only need 1 drive to make a RAID 10 or RAID 1 array, we just tell the Linux mdadm utility that the other drive is "missing" and we can then add our original drive to the array after booting into our new RAID array.
Step#1 Install tools we need
yum -y install mdadm rsync
Step #2 Create your partitions on the drive that will be our RAID array
Here I assume it is /dev........
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........
The strange thing is that usually the first install or two will work on any new machine but then it suddenly won't. I had this experience on QEMU 2.13 on a different machine. There is something finicky or buggy about the CUCM installer even when choosing the same virtual hardware specs.
qemu-kvm command:
/usr/libexec/qemu-kvm -version
QEMU PC emulator version 0.12.1 (qemu-kvm-0.12.1.2-2.506.el6_10.1), Copyright (c) 2003-2008 Fabrice Bellard
........
chroot which stands for change root allows you to virtually operate in another operating system even though you haven't booted it. It is commonly used to deploy new distros, applications and to fix a broken Linux/Unix install or prep a new system image without having to physically boot the drive or disk.
So in this example let's say we have a drive that has a Linux OS installed on /dev/sdb1 and we have mounted this partition on /mnt/sdb1
The key point is to edit the &quo........
The key thing is that you must use a "machine"id of "pc-1.3" or it will say your hardware is not supported.
Additionally you MUST use a virtio disk or you will get a ks_pre.sh error as soon as the install starts (a look at logs will show it can't find a disk). This is funny because even though the OS finds the disk and an fdisk -l shows it, it looks like the script looks for a /dev/vda device (virtio) and nothing else, so if you didn't use Virtio as you........
What you need to do if you have taken a dd or real raw image dump of a hard disk:
VBoxManage convertdd windows2019-eval-template.img windows2019.vdi --format VDI
The .img is the raw dd dump and the .vdi is the output file.
--format VDIspecifies to output to .vdi format
If you are in a pinch you can always use qemu-kvm binary and manually specify the .img as your disk and i........
The key thing here is to know the actual partition that is encrypted.
Often in Linux Mint's installer that ends up being partition 5 or /dev/sda5
sudo cryptsetup luksOpen /dev/sda5 anynamehere
You will then be prompted for your irrecoverable passphrase:
Enter passphrase for /dev/sda5:
If all goes well it won't say anything further. If it says ""No key available with this passphr........
Do you hate how Centos 7 defaults to allocating most of your valuable space to /home even though it is a production server?
Here is a quick guide on how to take back that space live, while online (of course make sure you have backups just in case something goes wrong!):
First we will reduce our home dir by 100G:
lvreduce -L -100G /dev/mapper/centos-home
WARNING: Reducing active and open logical volume to ........
size = the amount of RAM (m for megabytes)
/mnt/ram = the mount location of the ram disk (change to the path you want it mounted to)
mount -t tmpfs -o size=4096m tmpfs /mnt/ram/
Example test in an old server:
You can see that when reading if you don't specify bs1=M the read speeds are several times slower (eg. 450MB/s vs 2.1GB/s)
mount -t tmpfs -o size=4096m tmpfs /mnt/ram/^C
root@testserver:~# dd........
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........
You get errors like below and see you have all question marks for the permissions if you go to /run/user/1000/gvfs
If you try to access the mounted share such as anything mounted as gvfs like an SSH share in your file manager you may get an error like this. It generally means an interruption in communication or a fault with gvfsd has caused it.
Solutio........
Server Side Config
1.) First install nfs-utils
yum -y install nfs-utils
2.) Configure nfs share
Create a directory for your NFS share
mkdir /datastore
Create your NFS share in /etc/exports
echo "/datastore 10.220.101.0/24(rw,sync,no_root_squash)" >> /etc/exports
systemctl restart nfs........
dvd+rw-mediainfo /dev/sr0
INQUIRY: [ASUS ][BW-16D1HT ][3.00]
GET [CURRENT] CONFIGURATION:
Mounted Media: 11h, DVD-R Sequential
Media ID: RITEKF1&n........
nfs mount failed:
mount 10.10.2.20:/tmp/nfsmount /mnt/nfs/
mount: wrong fs type, bad option, bad superblock on 10.10.2.20:/tmp/nfsmount,
missing codepage or helper program, or other error
(for several filesystems (e.g. nfs, cifs) you might
need a /sbin/mount. helper program)
 ........
#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........
It has been a big pain for a long-time to install Windows from a Linux environment. I used to run a windows install server and it never worked right for some reason (the install would fail on most servers).
Before getting start be sure to setup your samba share so once you boot into WinPE you can mount the install for whatever Windows you want
/etc/samba/smb.conf
[smbwinstall]
path = /tftpboot/images/winstall
guest ok = yes........
Error: Unable to apply new quota values: quota not running
Container start failed (try to check kernel messages, e.g. "dmesg | tail")
Killing container ...
Container was stopped
Error: Unable to apply new quota values: quota not running
Can't umount /vz/private/123123: Invalid argument
[root@rtt 123123]# vzquota on 123123
vzquota : (error) Can't open quota file for id 123123, maybe you need to reinit........
yum -y install samba
vi /etc/samba/smb.conf
https://www.kernel.org/pub/linux/utils/boot/syslinux/syslinux-6.03.zip
mkdir syslinux;cd syslinux;unzip syslinux-6.03.zip
mkdir -p /tftpboot/libs/
cp bios/com32/modules/linux.c32 /tftpboot/libs/
cp bios/com32/libutil/libutil.c32 /tftpboot/libs/
cp bios/com32/lib/libcom32.c32 /tftpboot/libs/
#add lib path
echo "PATH libs" >> /tftpboot/pxeli........
guestmount -a kvmuserscra.img -m /dev/sda1 mount
libguestfs: error: mount_options: /dev/sda1 on / (options: ''): mount: unknown filesystem type 'ntfs'
guestmount: '/dev/sda1' could not be mounted.
guestmount: Did you mean to mount one of these filesystems?
guestmount: /dev/sda1 (ntfs)
guestmount: /dev/sda2 (ntfs)
yum -y install ntfs-3g
still........
myguy@devbox:~$ sudo mdadm -As
myguy@devbox:~$ cat /proc/mdstat |grep sdf
md125 : inactive sdf3[2](S)
sudo mdadm --manage /dev/md125 --run
mdadm: started /dev/md125
........
A great way if you have a bunch of drives and mdadm connected and are looking for backups/archives and don't know what is where!
for md in `cat /proc/mdstat|grep md[0-99]|awk '{print $1}'`; do mkdir /mnt/$md; mount /dev/$md /mnt/$md; done........
sudo mount -a
Unable to find suitable address.
[35758.706993] CIFS VFS: Error connecting to socket. Aborting operation.
[35758.707247] CIFS VFS: cifs_mount failed w/return code = -111
[35795.476160] CIFS VFS: Error connecting to socket. Aborting operation.
[35795.476346] CIFS VFS: cifs_mount failed w/return code = -111
When the above happens "Unable eto find suitable address" it usually means the smb nam........
The easiest way to recover or mount an off-line ecryptfs directory is the built-in command from ecryptfs
sudo ecryptfs-recover-private It will find your wrapped passphrase and ask for your password and mount it in tmp. Much easier especially when your current active OS is using ecryptfs too.
This a fantastic tool when going through old backups.........
This container won't start after exhausting its memory. There are no relevant or helpful messages in dmesg or vzctl.log as well. Standard troubleshooting such as disabling PPP etc has not helped.
2017-07-06T23:33:29-0400 vzctl : CT 888171 : Locked by: pid 166029, cmdline vzctl start 888171
2017-07-06T23:33:29-0400 vzctl : CT 888171 : Container already locked
2017-07-06T23:33:29-0400 vzctl : CT 888171 : Container was stopped
2017-07........
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!
If you have trouble booting after this check this CentOS mdadm RAID booting/fixing guide.
One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting
The nor........
user@box:~$ sudo tune2fs -l /dev/md99
[sudo] password for user:
tune2fs 1.42.9 (4-Feb-2014)
Filesystem volume name:
Last mounted on: /mnt/md50
Filesystem UUID: 976a8655-2619-4587-878c-dab07f7b7652
Filesystem magic number: 0xEF53
Filesystem revision #: 1 (dynamic)
Fi........
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........
*Update so this doesn't work it must be something to do with the path of nfs or something else but the installer fails with "Installer crashed" at the end whereas with the CD/USB it works.
This assumes you've already installed and configured a separate PXE/DHCP server somewhere else and your /tftpboot directory is setup.
This is for Linux Mint 18.1 but generally applies to most versions although you may have tro change things like "casper"........
ecryptfs-mount-private
Enter your login passphrase:
Inserted auth tok with sig [ee16d84] "into the user session keyring
mount: No such file or directory"
[ 156.118113] ecryptfs_mount: kern_path() failed
[ 156.118431] Reading sb failed; rc = [-2]
[ 164.233055] traps: mate-notificati[3472] trap int3 ip:7f43d7002c13 sp:7fff162c6600 error:0
[ 166.017061] ecryptfs_mount: kern_path() failed........
1.) Replicate the number of partitions in your new drives.
gdisk /dev/sda
gdisk /dev/sdb
I created 3 partitions of the same same size.
partition #1: +1G (/boot)
partition #2: +60G (swap)
partition #3: rest of it (/)
#note if you are using GPT/gdisk you need to create separate a partition at least 1MB in size (in my case I would a 4th partition and mark it type ef02).........
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........
This was a surprising bug but I unplugged all drives for an array md127. At first it was just 1 drive and mdadm seemed to notice this. I unplugged the second drive taking the array offline but mdadm did not realize it was offline and still showed a non-existent disk as being part of it. This created problems trying to unmount it or even to stop this array with mdadm freezing.
As for how to fix it I can only think of making sure you are not in a mounted path of........
Cannot even "Browse Network" when clicking on "Windows Network"
Unable to mount location
Failed to retrieve share list from server: No such file or directory
logs:
[2017/02/14 00:16:44.271314, 0] ../source3/nmbd/nmbd.c:58(terminate)
Got SIGTERM: going down...
[2017/02/13 17:35:41.797944, 0] ../lib/util/become_daemon.c:124(daemon_ready)
&........
It is already known this is not possible
mdadm --create /dev/md3 --level 10 --layout=f2 --raid-devices=2 /dev/sdc1 /dev/sdd1
mdadm: /dev/sdc1 appears to be part of a raid array:
level=raid10 devices=2 ctime=Sat Dec 24 18:44:29 2016
mdadm: /dev/sdd1 appears to be part of a raid array:
level=raid10 devices=2 ctime=Sat Dec 24 18:44:29 2016
Continue creating ar........
The only solution after trying many suggestions was to simply restart the "vz" service (definitely not preferable).
Even doing an ifdown and ifup for venet0 did not help.
ifup venet0
Bringing up interface venet0:
Configuring interface venet0:
net.ipv4.conf.venet0.send_redirects = 0
RTNETLINK answers: Network is down
Some errors from log:
CPT ERR: d2dc60........
md127 issue, it should be /dev/md3 per mdadm.conf
Any time something is mounted as md127 it almost always means there is no entry for this mdadm array in the mdadm.conf in initramfs (which is separate from your actual /etc/mdadm.conf).
cat /etc/mdadm.conf
ARRAY /dev/md3 metadata=1.2 UUID=b6722845:381cc94e:7a2c5b5f:8e3b7c4f
The reason for this is something strange, most Linux OS's bizarrely always keep their own copy of /etc/mdadm.con........
migrating from an old OpenVZ (Centos 5) to new OpenVZ (Centos 6)
Also if migrating from 32-bit HN to 64-bit your RAM will probably be much bigger than it should be!
16x bigger
eg. 32bit HN:
total used free shared buffers cached
Mem:&nb........
rm /vz/lock/1200.lck
rm: remove regular file `/vz/lock/1200.lck'? y
vzctl start 1200
Container already locked
vzctl start 1200
Starting container ...
vzquota : (error) can't lock quota file, some quota operations are performing for id 1200
vzquota on failed [7]
vzquota off 1200
vzctl start 1200
vzquota on 1200
root@rttbox ~]# vzquota off 1200
vzquota : (........
This happened while an mdadm array was syncing, all access from writing a new blank file to opening a small .txt file was very slow:
[222117.312078] kjournald starting. Commit interval 5 seconds
[222117.685060] EXT3-fs (md0): using internal journal
[222117.685096] EXT3-fs (md0): mounted filesystem with ordered data mode
[222122.376847] kjournald starting. Commit interval 5 seconds
[222122.602825] EXT3-fs (md2): using internal jour........
Iwill start by saying I think I know what caused this boot-time error on Linux Mint but should also apply to Debian and Ubuntu.
I changed my BIOS time to several hours in the past to match the current time, but this caused Linux to think there were incorrect filesystem times.
The problem is that it seems when you hit this I am not sure what is happening, it doesn't seem to be doing fsck and hangs without prompting the user.
What I have found is that........
Add the following to fstab where 192.168.1.125/Media is the samba share and where /home/homeuser/Downloads is where you want to mount.
Change user and pass to what is needed (if no pass is required it still works fine with the below).
//192.168.1.125/Media /home/homeuser/Downloads cifs user=guest,pass=bla 0 0
mount: wrong fs type, bad option, bad superblock on //192.168.1.125/Media,
&nbs........
In this case we want to mount partition #2
fdisk -lu Centos-6.6-x86_64.img
You must set cylinders.
You can do this from the extra functions menu.
Disk Centos-6.6-x86_64.img: 0 MB, 0 bytes
255 heads, 63 sectors/track, 0 cylinders, total 0 sectors
Units = sectors of 1 * 512 = 512 bytes
Device Boot&nbs........
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........
mount -o bind /somedir /anotherdir
In /etc/fstab
/somedir /anotherdir none bind 0 0........
Iwas surprised to see that Linux Mint at the latest 17.2 version still has NO mdadm installer option, and worse the installer will not be able to create a proper booting environment even when you do install it.
How to setup mdadm in Linux mint LiveCD
sudo su
apt-get install mdadm
# partition as you need and then create your mdadm devices
# create your SWAP md0
mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sda1 /d........
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........
libguestfs tools howto guide for managing virtual machine images.
libguestfs-tools aka guestfs tools has a lot of tools that make this very easy for you. You can easily mount partitons from an image with some of the commands below.
To mount a partition
#mount the kvmuser102821.img image and the /dev/sda1 partition from it to the local directory "mount"
guestmount -a kvmuser102821.img -m /dev/sda1 mount
........
Unable to mount iPad 4
Unhandled Lockdown error (-4)
This is because you need the libimobiledevice-utils package installed and a newer version of it.
My older Ubuntu 10.10 uses a version that does not have "idevicepair" which seems to work perfectly and automatically with newer versions of the library.
Basically if you install the above library it should be plug and play and if your imobiledevice-utils doesn't have 'idevice........
This is what fixed it:
[root@box13 ~]# dd if=/dev/zero of=/dev/md160 bs=512 count=500
Basically you need to wipe out more than just the 512 byte partition table so 512 bytes * 500 is more than enough to make DRBD happy and think the partition is now empty.
The reason this happens is because it gets confused when there is a previous partition with data on the device you are using.
root@box13 ~]# d........
#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........
sudo mount -o user /dev/sr0 cd
You need the "user"option otherwise non-root or non-owners cannot view the CD and this would make it so no anonymous access to the CD/DVD mount would work. Note that most distributions including Ubuntu DONOT work unless you manually mount and share as shown above (Icouldn't find any other way in Ubuntu).........
mount -o bind /proc /sda2/proc
mount -o bind /dev/ /sda2/dev
mount -o bind /sys /sda2/sys
chroot /sda2
mint / # mount -o bind /proc /sda2/proc
mint / # mount -o bind /dev/ /sda2/dev
mint / # mount -o bind /sys /sda2/sys
mint / # chroot /sda2
mint / # cd ~
mint ~ # ls
Desktop
mint ~ # cd /
mint / # ls
bin Desktop dev-temp home&nb........
Starting container...
vzquota : (error) Quota on syscall for id 42131: No such file or directory
vzquota on failed [3]
Solution
cd /var/vzquota
mv quota.42131 quota.42131-disable
vzctl start 42131
Starting container...
Initializing quota ...
Container is mounted
Adding IP address(es):
Setting CPU units: 1000
Container start in progress...
........
guestmount -a yourimage.img -m /dev/sda1 --ro /mountpoint
Change "yourimage.img"to the actual disk image.
Change "/dev/sda1" to the device on the disk image you want to mount.
--ro is specified only if you don't want write access (good to ensure you don't mess anything up if you just want to recover data).........
This is usually solved by two variables alone:
max_input_vars=5000
memory_limit=256M
Now you should be able to have unlimited amounts of custom menus in Wordpress.........
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........
mkdir: cannot create directory 'test': Disk quota exceeded
You are out of inodes usually:
df -i
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/simfs 200000 200000 0 100% /
none ........
Container is currently mounted (umount first)
The container is stuck in the "mounted" state, you must manually start it to get it out of that state (there is no umount option as implied by OpenVZ vzctl).........
When trying to reboot this Centos 5 container, it gets stuck as "mounted" and requires a manual start command, here is what dmesg shows:
[424458.173252] VE10000: no allowed mount options found for device 0:21
[424458.177970] proc: unrecognized mount option "relatime" or missing value
[424460.297663] CT: 10000: stopped
[426663.466433] CT: 10000: started........
vgchange -ay
3 logical volume(s) in volume group "vg_12" now active
lvscan
inactive '/dev/vg_12/lv_root' [144.04 GB] inherit
inactive '/dev/vg_12/lv_home' [1.00 GB] inherit
inactive '/dev/vg_12/lv_swap' [7.85 GB] inherit........
-bash-3.1# shutdown -rn now
Connection to localhost closed by remote host.
Connection to localhost closed.
Sometimes I work with embedded systems/custom kernels without any of the fancy init scripts and other common Linux basics that most would expect. This means that often the "reboot" command (which uses an init script) will never work, not only that but it will hang the server and a manual power cycle or reboo........
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........
df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg_12-lv_root
50G 1.2G 46G 3% /
tmpfs 7.8G 0&nb........
parted sdc.img
GNU Parted 1.8.8
Using /home/one/sdc.img
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) unit&nb........
I backed up everything in the /mnt/sd_card directory thinking that some dataloss could occur for some reason but purposely left my microSDHC unbacked up thinking that "it won't touch that since it's external" and Samsung's and other manufacturers website even say this (that it won't be affected and not to worry etc).
Apparently I was wrong, my microSD was "undetected" and asked to be formatted after the upgrade (there goes 3-months worth of family photos). No........
Disk /dev/sda: 320.0 GB, 320072933376 bytes
256 heads, 63 sectors/track, 38761 cylinders
Units = cylinders of 16128 * 512 = 8257536 bytes
Device Boot Start End Blocks Id System
/dev/sda1 1 38........
Directadmin Error when changing user settings/saving
Details
Error with system Quotas
setquota: Mountpoint (or device) / not found. setquota: Not all specified mountpoints are using quota.
Debug Guide
You have to disable and enable the quota's using vzquota on and off.
After that it will work.........
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........
fdisk -lu VPS.img
last_lba(): I don't know how to handle files with mode 81ed
You must set cylinders.
You can do this from the extra functions menu.
Disk VPS.img: 0 MB, 0 bytes
255 heads, 63 sectors/track, 0 cylinders, total 0 sectors
Units = sectors of 1 * 512 = 512 bytes
Device Boot Start End ........
This is one in a series of weird things whichIthought was motherboard related (I RMA'd the motherboard), the RAM tests fine with memtest86 and I used badblocks on both RAID 1 members with no errors and smartctl is happy with them.
Basically the array crashes the kernel a lot and has issues when writing.
[112322.723465] md0: rw=0, want=14958668696, limit=1887460480
[112322.731077] attempt to access beyond end of device
[112322.731087] md........
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........
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........
high IO wait
424 root 39 19 1900 848 552 D 0.0 0.0 0:00.91 updatedb
root 424 0.0 0.0 1900 848 ? DN Mar11 0:00 /usr/bin/updatedb -f sysfs?rootfs?bdev?proc?cpuset?binfmt_misc?debugfs?sockfs?usbfs?pipefs?anon_inodefs?futexfs?tmpfs?inotifyfs?eventp........
There are all kinds of threads and links on the internet, and this seems to be a contentious issue butI don't know why.
95th percentile is either a good deal for some or a big rip off for others, Ijust said it there :)
But the reality is that for MOST people who transfer low amounts of data but burst to higher speeds such as 40mbit+ even for short periods of time, then you'll pay a lot of money to do that.
Basically 95th percentile is an-old archaic method........
umount: /home/diret/mount: device is busy.
(In some cases useful info about processes that use
the device is found by lsof(8) or fuser(1))
I tried everything (fusermount -u) to unmount it but the only thing that worked was actually doing this:
ps aux|grep sshfs
Then I identified the sshfs connection and did:
kill -kill pid........
I've only used it on Centos, soI thought I'd make a quick Debian guide:
Install the DRBD Package
apt-get install drbd8-utils
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
libswfdec-0.8-0
Use 'apt-get autoremove' to remove them.
The following........
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........
Moving to RAID was a pain.
What you have to do is the following from an existing install:
Install mdadm
Create your mdadm RAID 1 array on your spare hard drive.
Start it with the missing disk.
rsync the entire contents of your current / to the md partition.
Here's a good way of doing it:
rsync -Pha --exclude=/proc/* --exclude=/sys/* --exclude=/mnt/* /. /mnt/md2........
From a LiveCD or if you're doing something like converting your non-RAID install to mdadm here's how you would chroot properly (you have to mount your proc, sys and dev on the running system/LiveCD to your chroot environment if you want things to work right, especially if you need to run update-initramfs due to a driver change etc..)
*replace "path" with your mount/chroot path
mount -o bind /proc /mnt/path/proc
mount -o bind /dev/ mnt/pa........
This is an SFTP mount that does not work or prompt for password.
Error: DBus error org.freedesktop.DBus.Error.ServiceUnknown: The name :1.1127 was not provided by any .service files
Please select another viewer and try again.
It seems to me that the connection often times out after being opened and the application doesn't know how to handle the disconnection and doesn't realize it needs to kill the instance and restart the connection.........
Adding IP address(es): 192.168.5.8 192.168.5.9
Setting CPU units: 1000
Error: undump failed: Invalid argument
Restoring failed:
Error: iptables-restore exited with 2
Error: Most probably some iptables modules are not loaded
Error: rst_restore_net: -22
Container start failed
Stopping container ...
Container was stopped
Container is unmounted
Error: Failed to undump VE
Resuming...
vzquota : (erro........
I am a huge fan of Linux and the idea of OpenSource but I've said it many times, there are still hurdles in today in 2010 for Linux as a Desktop. Linux is still intended for servers at its very core. This can be changed succesfully though, as Apple has shown us with Mac OS X based on FreeBSD.
Half of the issue is lack of driver support and the other half is the Linux Kernel and Window Manages, KDE and GNome still both don't cut it (but they're getting closer).
I'll........
Different distributions such as Debian and Centos behave differently when trying to shutdown your system.
shutdown -H now on Debian does not do what you'd expect. The system won't power down, it will halt and do everything but power down.
shutdown -PH now will do the job though (actually power the system off). This is important to test especially if you are not near the system. If you just use -P it forcefully shuts off which is not........
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........
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!........
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........
Why would you want to downgrade the superblock? Old mdadm verisons like mdadm 2.5.6 only use the 0.90 superblock/metadata and new versions use 1,1.0,1.1 and 1.2 superblocks by default.
There are some annoying caveats with this, first of all the new superblocks (later than 0.90) CANNOT be read by GRUB, so you won't even be able to install GRUB. Even worse, old versions of mdadm CANNOT automatically detect arrays even if they were created with a new version of mdadm with th........
I have an md0 arary that my Centos install refers to. I feel this is half the reason why it won't boot anymore.
I saw the initrd for Centos was assembling it as md127 even though it was known as md0.
The reason for this is because I used mdadm --assemble --scan to detect the array on a LiveCD. I had no idea this name would stick (but now I realize the name is permanently stored in the metadata once you mount md127 or whatever random name assemble gives it). W........
Partclone is a great tool that is basically like dd only it does not waste space, it doesn't take the whole partition, yet it does the same thing as dd, only with huge space/cost savings.
Clonezilla uses partclone and is more of an integrated/easy to use suite I guess you could say. I've personally only used partclone but I wish there was an easy way to mount partclone images.
I believe with Clonezilla you can do that, so I will probably give it a shot next time.........
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........
I installed 5.5 with a 300GB RAID 1 partition (boot is also on this partition). It booted up fine the first few times until after I used a Live CD and accessed the array, and it became named /dev/md127 for some reason.
Now whenI boot into CentOS I get a kernel panic and different errors, once I got "invalid superblock", even though the array is fine (it didn't happen again, probably because I was sure to dismount and stop the mdadm array properly).
Here's what........
It's not just as simple as running the chroot command, you need to ensure the /proc and /dev entries are passed through and populated to the chroot environment.
Step 1 - Mount Your Off-lineOS
mount /dev/sda1 /mnt
Step 2 - Mount Proc
mount -t proc none /mnt/proc
Step 3 - Mount Dev
Most guides will tell you to use this: mount -o bind /dev /mnt//dev but that doesn't work for some reason in many cases:
mount: wron........
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........
I have no idea why but mkfs.ext3 defaults to a patheticlly small blocksize of 1024 bytes/1KB (kilobyte). That means the maximum filesize is ONLY 16GB! With 2KB/2048 bytes you get a 256 GB maximum filesize, and with 4KB/4096 bytes you get 2TB!
I finally noticed/paid attention to this after realizing that with rsync and scp that no file larger than 17GB could be transferred. I then realized it must be a file size limit on the partition.
Here is what tune2fs tol........
Proxmox has made this free utility to backup running OpenVZ containers. It's a great program which is actually just a PERL script but gets the job done. This program is not 100% required because all it really does is cp -a from your container's path as far as I know but it is still good to have uniformity to how you backup your containers.
For RPM distros such as Centos/RHEL/Fedora etc.. download and install this:
wget http://www.proxmox.com/cms_proxm........
./ntfs-3g /dev/sda1 /mnt -o force
Unexpected sectors per cluster value (127).
Failed to mount '/dev/sda1': Invalid argument
The device '/dev/sda1' doesn't seem to have a valid NTFS.
Maybe the wrong device is used? Or the whole disk instead of a
partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?
This is happening on a system I've come across an HP 6930P running Windows XP Professional. The partition appears to be very norm........
heartbeat is stopped for some reason
Anyway hnode2 was active and the services are running fine but I see heartbeat has been stopped somehow.
Here is the last log I see of heartbeat:
[quote:23c84415f5]
Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: MSG stats: 9/1762471 ms age 0 [pid16738/MST_CONTROL]
Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: cl_malloc stats: 716/51784021 152624/74519 [pid16738/MST_CONTROL]
Sep 9 17:15:32........
PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist:
[code:1:1fd0f3abbe]
if (!file_exists($OPENSSL)) {
//echo "ERROR: OPENSSL $OPENSSL not foundn";
}[/code:1:1fd0f3abbe]
I don't get itI can clearly see the contents of /usr/bin by using the PHP system fu........
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........
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........
Mounting NTFS in UnixJust a quick tutorial to mount your NTFS volumes in Unix (FreeBSD/Linux)
[quote:4a9de7bf80]mount -t ntfs -o umask=0 /dev/your_partition /mnt/your_mount_point[/quote:4a9de7bf80]
[b:4a9de7bf80]-o umask=0[/b:4a9de7bf80] is to ensure all users can access the mounted partition (otherwise don't use it and only root can access the mounted partition)
[b:4a9de7bf80]-t ntfs[/b:4a9de7bf80] is simple because it just lets mount kno........
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........
top - 09:34:12 up 2 days, 20:57, 2 users, load average: 1.83, 1.99, 2.03
Tasks: 59 total, 2 running, 57 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.3%us, 0.0%sy, 0.0%ni, 0.0%id, 99.7%wa, 0.0%hi, 0.0%si, 0.0%st
That 99.7% wa is iowait, it means the server is waiting for a process to complete an IOoperation or in plain English, there is a delay in........
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........
I've tried to find a good sensible solution to cluster with and each technology has it's pros and cons and there is no perfect solution and I've found a lot of "exaggerations" in the applications, benefits and performance of these different filesystems.
DRBD
I first started off with DRBD and Ihave to say it does live up to the hype, is quite reliable (although it can be annoying to match up the kernel module and user applications since they must match and whe........
To enable Fuse to work inside a OpenVZ container it's very simple (although some people say it can't be done).
Remember that on your HN(HostNode) for OpenVZ, Fuse must be installed and the module must be loaded for this to work. In addition remember that you need the Fuse package installed inside the container of course.
vzctl set 2000 --devices c:10:229:rw --save
vzctl exec 2000 mknod /dev/fuse c 10 229
The part that most people forget........
The dmg format is silly and annoying to work with, why couldn't Apple stick with the .iso standard? Anyway, there's an excellent Linux and Windows based tool to convert it back to a normal .iso Image called dmg2iso
I'll only cover theLinux version although the Windows pre-built binary works the same way.
Download dmg2iso here for free (from the author's website)
It's just silly and doesn't make sense that Ubuntu doe........
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........
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........
This will give you the basic info needed to browse and connect to Samba shares from the command line. From the GUI of Gnome or KDE etc, it is pretty standard and straight forward. However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go.
First get a list of all the Samba/SMB shares on the target.
smbclient -L hostname........