If I have two (virtual) servers online (ie out in the real world, not on my LAN or behind ADSL connections) and I want one to be used to backup the other, what method would anyone suggest? I'm thinking of data backups rather than disk images.
I'd like (a) to have rolling backups so I can roll back to before any specific **** up, (b) to have a sensible way to backup MySQL databases
I can't think of any other specific requirements.
Bandwidth between the two servers isn't a major issue but not something I want to ignore completely. Similarly disk space isn't a problem, but wasting it by having multiple copies of unchanged files would still be a bit silly. On the other hand, both servers will have public IPs and therefore I need to consider the security implications of opening up the live server so that the backup server can access it, and (to a lesser extent) vice versa.