Linux comes with the cryptsetup command. It is used to setup dm-crypt (transparent disk encryption subsystem in Linux kernel) managed device-mapper mappings. This shell script can be used to mount dm-crypt based partitions with passphrase:

# A simple shell to mount disk encryption based parition under Linux.
# Tested on Debian and Ubuntu base NAS servers.
# ----------------------------------------------------------------------------
# Written by Vivek Gite <>
# (c) 2008 nixCraft under GNU GPL v2.0+
# ----------------------------------------------------------------------------
# Last updated: 05/Dec/2011
# ----------------------------------------------------------------------------
### commands ###
### SET ME FIRST ###
### Partition specific settings ###
### SET ME FIRST ###
_mnts="/dev/cryptvg/mybackup "
${_crypt} luksOpen ${_device} $_name
${_vg} --mknodes
${_vgc} -ay
${_mnt} ${_mnts} ${_mntd}

This script is stored on our nas server. All backups are on RAID-6 disks are encrypted. The nas server is online 24×7. After rebooting the server you need to run this script to mount the dm-crypt based partition. A sample session is as follows:
$ ssh
$ sudo /usr/local/sbin/mount.crypt

Sample outputs:

Enter passphrase for /dev/md3: 

  Reading all physical volumes.  This may take a while...
  Found volume group "cryptvg" using metadata type lvm2
  1 logical volume(s) in volume group "cryptvg" now active

Verify disk space and newly mounted partition:
$ df -H
Sample outputs:

Filesystem             Size   Used  Avail Use% Mounted on
/dev/md0               127G   930M   120G   1% /
tmpfs                  1.1G      0   1.1G   0% /lib/init/rw
udev                   1.1G   267k   1.1G   1% /dev
tmpfs                  1.1G      0   1.1G   0% /dev/shm
/dev/md2               1.6T    88G   1.5T   6% /data
                       635G    59G   544G  10% /securebackup
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1 comment… add one
  • Dinesh Dec 14, 2011 @ 14:15

    Hi folks,

    Any body having goood snmp notes with all it command. I apreciate if anybody provides asap.

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