Ubuntu: Using compression on your tape backups

  If you have compressible data you may save space on you tapes by using compression; this comes at a cost of CPU cycles to do the compressing, which can often be a worthwhile tradeoff for a long-term backup. To do this is quite simple – add in the -z switch to your tar command. […]

Ubuntu: Using tar to span a backup across multiple tapes

  Following on from the article on writing files to a tape backup, what happens if you want to back up more than what fits on a single tape? Here we want to use the –multi-volume switch, or -M. Use it so:   tar -cvMf /dev/[path-to-tape] [backup folder or files]   As a working example: […]

Mediawiki 403 forbidden errors after upgrading to Ubuntu 13.10

  A customer upgraded from 13.04 to 13.10 and their internal wiki was broken afterwards; for a simple Apache install where the wiki was installed at the web root and all access was via the LAN (thus they were happy with not restricting the access), the fix was to add:   <Location /> Require all […]

ZFS on Linux (Ubuntu) – arcstat.py is now available! How do you run it?

UPDATE: This information is now out of date, see new post here.   One very handy ZFS-related command which has been missing from the standard ZFS on Linux implementation has been arcstat.py. This script provides a great deal of useful information about how effective your adaptive read cache (ARC) is.   ZFSoL 0.6.2 includes it, […]

Ubuntu: How to check the samba version

  To check the version of Samba that you are running, use the smbstatus command. The first line is the version, which should look something like:   Samba version 3.6.3   If you want to see just the version without the rest of the smbstatus information, you can run:   smbstatus –version   Much less […]

Where is the crontab in Ubuntu?

  If you’re looking to make a copy of a user’s crontab as a backup or just to view it without using the crontab editor, you can locate it at:   /var/spool/cron/crontabs   Each user’s crontab will be in this directory in a file named as their username (e.g. root). If you’re working with a […]

Ubuntu: How to restore your files from a tape

  This is just like extracting a regular tar archive:   tar -xvf /dev/[path to tape] [directory or file to restore]   e.g.:   tar -xvf /dev/st0 backups   This will restore the “backups” file/folder to the current working directory. To check your current directory, you can use:   pwd   to make sure that […]

Ubuntu: How to write files to a tape

  To put files onto a tape, run the following:   tar -cvf /dev/[path to tape] [file or directory] [file or directory] [file or directory]   An example would be:   tar -cvf /dev/st0 /home/bob   This will back up the user bob’s home directory to the tape, here located at /dev/st0 (a typical location […]