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........
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........
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........
It sounds intuitive that you may just move the /var/lib/docker dir to another location and symlink it back but it won't work and you'll get an error.
How to move Docker Storage the Correct Way
This assumes that you want to use /mnt/raid as the new location.
1.) Stop Docker
systemctl stop docker
2.) Move /var/lib/docker
mv /var/lib/docker /mnt/raid/
3.) Edit the Docker daemon file
Specify the path you wan........
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........
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.........
$ ./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........
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........
dd is a very handy tool and there are some more practical things we can do. For example if we want to dump a 3TB drive and want to preserve it and only 200GB are being used on the 3TB we can save a lot of space with gzip.
Backing Stuff up with dd
How to Use dd to backup a raw hard drive and tar gzip at once
Change /dev/sda to the drive you want to backup
Change /mnt/extras........
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........
WARNING: Image format was not specified for '/mnt/space/cucm12.img' and probing guessed raw.
Automatically detecting the format is dangerous for raw images, write operations on block 0 will be restricted.
Specify the 'raw' format explicitly to remove the restrictions.
#you should manually specify the format
q........
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........
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........
sudo apt-get install libcurl4-openssl-dev git build-essential autotools-dev autoconf libcurl3
sudo apt-get install libcurl4-gnutls-dev
git clone https://github.com/wolf9466/cpuminer-multi
sudo apt-get install cmake libpthread-* libmicrohttpd-dev libssl-dev libhwloc-dev
git clone https://github.com/fireice-uk/xmr-stak-cpu.git
make install
cd bin
chmod +x xmr-stak-cpu
./xmr-stak -O xmr........
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........
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........
When using the .sh script the rendering doesn't work after an upgrade of related packages to kdenlive.
kdenlive (kdenlive:amd64 (4:17.04.1+git201705191233~ubuntu16.04.1)) with affine or composite transitions was fine but is now broken during the time of transition it is just a white screen.
The previous version was fine:
kdenlive:amd64 (4:17.04.1+git201705191233~ubuntu16.04.1
But now I can't find it or install it:........
Solution:
Aptitude is very smart and fixed the issues it was because of nvidia cuda and opencl and nothing else suggested or hinted this using apt
sudo aptitude install wine
The following NEW packages will be installed:
ocl-icd-libopencl1{ab} ocl-icd-libopencl1:i386{ab} wine wine1.6
wine1.6-amd64{a} wine1.6-i386:i386{a}
The following packages will be REMOVED:........
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........
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........
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........
mv -f /home/user/Downloads/android-studio/ /mnt/sda3/
mv: inter-device move failed: ‘/home/user/Downloads/android-studio/’ to ‘/mnt/sda3/android-studio’; unable to remove target: Is a directory........
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........
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........
rsync -Phaz --exclude=/dev/* --exclude=/sys/* --exclude=/proc/* --exclude=/mnt/md126 / /mnt/md126........
#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........
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........
Sep 26 16:56:21 box kernel: 00 00 00 00 00 00 00 00
Sep 26 16:56:21 box kernel: [37007.155690] d_alias libdl-2.12.so d_count=9 d_flags=8
Sep 26 16:56:21 box kernel: [37007.155697] 09 00 00 00 08 00 00 00 9f 05 9f 05 00 00 00 00 c0 71 1d 18 04 88 ff ff 00 00 00 00 00 00 00 00 a0 7e 48 00 00 c9 ff ff 78 a9 21 18 04 88 ff ff 3a 7b fa 4e 0d 00 00 00 98 5c 2d 18 04 88 ff ff 18 5c 2d 18 04 88 ff ff 18 5c 2d 18 04 88 ff ff 00 01 10 00 00 00 ad de 00 02 20 00 00 00 ad de f8........
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........
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........
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........
Go into the directory for your Virtual Machine and delete all ".lck" directories.
rm -rf *.lck
After that your server should boot.........
The Xen VPSI had was not working properly and when they asked for the login information I found the support was coming directly from India:
whois 122.178.148.*
[Querying whois.apnic.net]
[whois.apnic.net]
% [whois.apnic.net node-5]
% Whois data copyright terms http://www.apnic.net/db/dbcopyright.html
inetnum: 122.178.128.0 - 122.178.191.255
netname:&........
Nov 29 20:17:58 ubuntu kernel: [ 1157.180789] md: md1 stopped.
Nov 29 20:17:58 ubuntu kernel: [ 1157.180829] md0: unknown partition table
filesystem not responding/reading properly with du or rsync (this needed an fsck).
[ 2571.489217] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923106
[ 2571.942299] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923110
[ 2571.9568........
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 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!........
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........
This was unbelievable how much the Xen kernel slows things down, keep in mind both tests were done on the hostnode, one was with the Openvz-Xen hybrid kernel and the other was just OpenVZ. You can see the performance difference is nearly 300% better when not using the Xen kernel.
OpenVZ-Xen Kernel Test Results (I was wondering what was wrong/so slow with my Core i5!)
# # # # # #&n........
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........
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........
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........
./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........
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........
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........
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........