How to Backup:

To backup your KnoppMyth box, run mythbackup as root. This stops the backend, so don't do this if you're recording something important. The idle.sh script attached to this page can be used to check for current activity and upcoming recordings either interactively or automatically.

An auto backup system can be made using the idle.sh and the mythbackup scripts. See AutomatedBackup for more details.

The mythbackup utility place two backup files (mythconverg.sql.gz and savedfiles.tar.gz) in the /myth/backup directory. You may want to copy these files to a safe place, such as a network share, a CD-ROM, or a USB stick before doing anything drastic to your MythTV box. See the LinuxTips page for the commands needed.

If your system is not functional, you may still have options to do a backup.

Old Backup (R5B7 and prior)

Things backed up:

/etc/mythtv/modules
/home/mythtv
The mysql database

Notable things not backed up:

/etc/X11/XF86Config-4
/etc/modules.conf

To see exactly what is backed up:

tar jtvf /myth/backup/mythtv.tar.bz2

Converting an old style backup to a new style backup:

cd /
tar jcvf /myth/backup/savedfiles.tar.bz2 ./etc ./root ./home

New Backup (R5C7 and later)

Things backed up:

/etc
/root
/home
The mysql database

To see exactly what is backed up:

tar jtvf /myth/backup/savedfiles.tar.bz2
tar ptvf /myth/backup/savedfiles.tar.gz

Note that not all of these things are restored automatically, but they are available for you in the backup. The list of files which is restored can be customized to add additional files. See this posting in the KnoppMythForums for more details on the new backup and restore: http://mysettopbox.tv/phpBB2/viewtopic.php?t=10117

How to Restore

Upon installation, if you choose "Auto Upgrade", and the files are in /myth/backup, most of them will be automatically restored.

First, if you have moved or copied the backup files somewhere besides /myth/backup you'll need to copy the backup files back there. When the backup files are in place, run mythrestore as root.

To restore individual files that were not restored

For example, to restore the config for lirc:

test first with
tar ptvf /myth/backup/savedfiles.tar.gz ./etc/lirc/lircd.conf
make a backup
cp /etc/lirc/lircd.conf /etc/lircd.orig
then restore files as needed
tar pxvf /myth/backup/savedfiles.tar.gz ./etc/lirc/lircd.conf
tar pxvf /myth/backup/savedfiles.tar.gz ./home/mythtv/.mythtv/lircrc
tar pxvf /myth/backup/savedfiles.tar.gz ./etc/lirc/hardware.conf

If your backup was out of date, you may have orphaned videos in your myth/tv folder. To make these videos available for viewing you'll need to download the source distribution of mythtv and run myth.rebuilddatabase.pl --dbhost=localhost, which is located in the contrib directory. This adds the missing videos to the database. You'll be prompted to enter names for the orphaned videos.

UPDATE: for R5C7

The script myth.rebuilddatabase.pl was originally written to look for .nuv video files. In recent versions of Mythtv, video is recorded into .mpg files, so this script falls flat on its face unless you add a command switch to the end to deal with mpg files:

myth.rebuilddatabase.pl --dbhost=localhost --ext mpg

Validating your backup

This attachement is a script to check the validity of a new style backup versus the current contents of the filesystem and mythconverg db: check_backup.sh Please note that this only works for new style backups and you only need it if you're upgrading from a version prior to R5D1 which doesn't already include one.