GIT as a backup tool
On a server, install git
cd /
git init
git add .
git commit -a -m "Yes, this is server"
Then get /.git/ to point to a network drive (SAN, NFS, Samba whatever) or different disk. Use a cron job every hour/day etc. to update the changes. The .git directory would contain a versioned copy of all the server files (excluding the useless/complicated ones like /proc, /dev etc.)
For a non-important development server where I don't want the hassle/cost of setting it up on a proper backup system, and where backups would only be for convenience (I.E. we don't need to backup this server but it would save some time if things went wrong), could this be a valid backup solution or will it just fall over in a big pile of poop?
You're not a silly person. Using git as a backup mechanism can be attractive, and despite what other folks have said, git works just fine with binary files. Read this page from the Git Book for more information on this topic. Basically, since git is not using a delta storage mechanism, it doesn't really care what your files look like (but the utility of git diff is pretty low for binary files with a stock configuration).
The biggest issue with using git for backup is that it does not preserve most filesystem metadata. Specifically, git does not record:
- file groups
- file owners
- file permissions (other than "is this executable")
- extended attributes
You can solve this by writing tools to record this information explicitly into your repository, but it can be tricky to get this right.
A Google search for git backup metadata yields a number of results that appear to be worth reading (including some tools that already attempt to compensate for the issues I've raised here).
etckeeper was developed for backing up /etc and solves many of these problems.
I've not used it, but you might look at bup which is a backup tool based on git.