On Thu, 2018-05-03 at 09:04 -0700, Chris Miller wrote: > Hi Folks, > > I have three questions. > > > > First, I need a "Theory of Operation" tutorial. Amanda has a lot of > moving parts, and I don't have a very clear understanding of what > they are or how they work. If I had a better understanding, I might > be able to answer a lot of my own questions. For example, If Amanda > is backing up to a NAS, can Amanda simply direct that client to that > NAS, or must Amanda get in the middle, thereby doubling the network > traffic -- one file transfer from the client to Amanda, and a second > from Amanda to the NAS?
The traffic goes through Amanda. The vTapes need to be mounted on the server. > Can Amanda create one vTape per backup, which vTape will be the > correct size for that backup or must they all be per-arranged? You > get the idea... > > vTapes have to be pre-prepared. And, afaik, they all have to be the same "size" because Amanda just thinks they're another kind of tape. You can always tell it that it can use more than one "tape" per backup run, though. > > > Second, I need to read tutorials on configuration for disaster > recovery, meaning backups that can be "bare-metal" restored -- on > both Microsoft Windows and Linux systems? Of course, taking the > backup is only half the problem; restoring the backup is equally > important... Restores are effectively manual. There is no fire-and-forget bare-metal restore process. You need to prep the filesystems and then restore them one-by-one through Amanda (or from the backup images themselves; they're just tarballs with a short header prepended). I find it helpful to keep documentation on filesystem sizes and layouts handy. I don't backup any Windows machines so can't comment on that. The one time I tried to use the Zmanda Windows client I couldn't get it to make a backup that was restoreable at all. > I run a backup every night. My other backups are differential > filesystem Sunday night through Thursday night, full filesystem on > Friday night, and disk image on Saturday night. I need Amanda to > conform to this schedule. If I ever grow to where I am backing up > many systems and time and space are critical resources, then I will > have justification to spend more time and have more faith in Amanda, > but for now my own bandwidth is the critical resource. > > Please don't scold me because I don't understand that Amanda is very > good at doing what I am preventing Amanda from doing and I should > simply let Amanda do what Amanda does best; I know that, but allowing > Amanda to do this means that I have to understand two different > backup paradigms. Please don't scold me because I could simply use > tar or some other technique and write my own scripts. I know this as > well, but that small development requires debugging and Amanda > already has this stuff debugged. I don't want to discover that my > scripts have a bug at some sub-optimal time -- during a disaster. That's a perfectly reasonable list of things to want, but Amanda doesn't do that. It schedules full or incremental backups as it sees fit to spread backups over your backup period. And it doesn't do disk- image backups, only filesystems. Amanda is built to backup the same list of filesystems to a pool of actual tapes over and over again. It has some plugins to do a little more and it can pretend chunks of disk are tapes, but effectively, that's all it does. It does it really well and reliably, but it's not the tool you seem to want. If I was only backing up to disk, I wouldn't use Amanda at all, I'd just use Restic over sftp direct to the NAS. It'd save a lot of disk space and a lot of network traffic.
