When I went to the Wiki, and searched for backup, I could only see the “snapshot” backup feature.
I’m assuming “snapshot” works somewhat similar to LVM snapshots, i e it takes a snapshot of the file system data structure at the time, and locks it down, but it’s still data on the same physical file system as the main site.
Further, I assume that the shared host machines either use some RAID array with moderate redundancy (RAID 5 or 6), or use a partition of some SAN box with similar redundancy.
So, if I’m wrong so far, please let me know. Now, given this, my question is:
Am I correct in understanding that there is no off-device backup of my account at dreamhost? If the underlying file system block device were somehow wiped (say, an EMP on the RAID array :-), then that’s all she wrote and I’d better have an off-site backup?
Then the follow-up question is: If it’s a RAID 5/6 style array, what’s the ratio of redundancy to capacity? How many disks, out of how many total disks, need to go out before data becomes lost?