> On Wed, Oct 09, 2002 at 04:53:55PM +0200, Toralf Lund wrote: > > Well, no matter what I do, I need *some* way to label new tapes without > > > too many '-f's etc. Also, I know some people are using separate configs > > > for permanent backups, but it seems like this requires a lot of > additional > > work, > > Not nearly as much extra work as trying to coerce amanda into running > in a fashion she's not designed to, such as tying specific tapes to > specific days of the week or mixing standard and archival backups within > a single config. > > > and also introduces the risk of not having the same directories > > backed up on "normal" and "archival" runs (which is essential.) > > Easy fix: Make Archive/disklist a link to Daily/disklist. Two configs > both reading the same list of directories to back up. Risk averted. > > > Well, maybe I should just use 10 or something (4 runspercycle + 1 extra > > > tape * 2), but what tapes will be used, then? > > All of them. Tape labels are meaningless to amanda. > > > How does Amanda decide what tape to use next, and what tapes are > > considered active, when there are more than "tapecycle" different > labels? > > amanda will request the least-recently used tape. If there are more > than <tapecycle> tapes labeled, she'll accept a freshly-labeled tape or > any tape that's not in the <tapecycle - 1> most-recently used. > > So now you're probably thinking, "Well, in that case, I'll do MonN > through > ThuN for the first three weeks, then Mon-Oct02 through Thu-Oct02 for > the fourth week." Yes, it'll probably work, for some value of "work". > But it will cause all kinds of additional problems. The two which spring > to mind offhand: > > - As was mentioned earlier, your tapes won't stay synchronized to the > calendar. If Monday is a holiday and the tape doesn't get switched, > amanda will ask for the Monday tape on Tuesday. Doesn't really matter. The day names are just meant to make it easier for the person managing the tapes (not me) to know which one to bring. I thought about using labels of the form <week no>.<run no> or simple sequencing, but I decided that would be more confusing.
> - Until a level 0 runs for a partition in week 1, it will have > incrementals based off the previous week 4's data. Same for week > 4 having increments from week 3. You really don't want to do that. > At best, having incrementals in one tape class (daily or archival) that > reference backups in the other class is useless. At worst, it can make > it a real PITA to try and figure out where to find your data when you > need to restore from the backups. Forgot to mention this earlier: I'm not using incrementals at all. Tapes from the same week will contain full backups of different directories, and a given file is backed up (only) once a week. Not ideal, but our typical files are very large and at the same time not too hard to recreate, so the cost of having enough tape capacity to back up everything more often can't be justified. I've considered adding a tapeless config with higher backup frequency for some of the data, though... - Toralf
