Yes, it's one of those exciting blog posts. Nevertheless, it's an important topic, so I thought I'd share some of my thoughts and findings on the various solutions available to help you sleep at night.
WP S3 BackupsThis WordPress plugin is a non-starter if you run a network. It may well do the job, but it's useless to me as it wants each individual site to have its own setup. Either way, you can check out WP S3 Backups for yourself.
VaultPressThe only commercial option I'm looking into. I like the idea of VaultPress: a plugin that constantly backs up your site to their cloud servers. The basic plan comes at just under a tenner a month, and basically gives you everything you'd need. Except of course, for this little tidbit:
Each site within your Multisite network will require its own subscription, just like individual sites. If you’d like to activate VaultPress on another site in your network, you’ll need to purchase a plan.
This looks to be very popular. It's clearly written by people for whom English is not a first language. This is of course not a problem, except for the exclamation marks everywhere!!!!!!!!!
It actually looks to be an amazingly robust plugin: insanely full of features, with extensive logging and easy management, and with an interface that slots right in with the WordPress dashboard.
It's a problem for one of the networks I manage though, as it has some large files which our current setup (using suPHP) doesn't like, because the script takes too long to process. However I urge you to check it out.
Shell scriptingThe non-plugin way to go would be to create a shell script that does the job. I've looked into a Python script because it's important that backups be uploaded somewhere externally - otherwise, what's the point in having them? - and there's a good Python module for Amazon's S3 cloud storage system.
There's a Python script available, but unfortunately it doesn't seem to work (it seems to create the archive, but throws an exception when trying to restore it). For some reason the developer chose to create his own TAR-based archive, rather than just using a standard TAR file which possibly would've lessened the problems.
ConclusionI'm going to plump for the BackWPUp option I think. It'll mean reworking how one of the networks is served, but for other reasons this seems like the right way to go. My own personal network is much smaller, so I'll probably get it running there first, but as it has such a large community behind it, I'm confident it'll do the job.
Do you have a preferred backup option that I've not listed? Let me know!