I want to use Turnkey / MediaWiki, but how can i backup my data and how can i restore it ?
Currently we don't recommend any particular method since which method is right for you often depends on your specific set of circumstances (e.g., what you want to backup, where you want to backup to, how frequently you want to backup).
Assuming you just want the content from your MediaWiki, an SQL dump of the database should suffice. You can get that either by using the mysqldump command from the cli, or using the phpmyadmin interface which is available on the most recent versions of LAMP based appliances (e.g., MediaWiki)
I will however give you some pointers regarding a full system backup. If you've installed
an appliance into a VM, you can usually backup/restore your VM as a single file (usually several hundred megabytes in size). How to do that depends on which particular virtualization software you are doing - consult the documentation.
Of course, you can also backup/restore your system as you would any other "from the inside" by archiving your filesystem into a tarball and later extracting it to restore. As described in the link above, the only catch is that there are a few special directories you usually don't want to add to your archive: /proc /sys /mnt /media/
Personally I find duplicity to be one of the best backup programs available (e.g., supports incremental backups, encryption, S3).
Whatever backup system you go with, remember to always give it a practice run to make sure it works. Don't be afraid to experiment!
Hope that helps!
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