Gene, > I'm puzzled, 4 days, but 5 tapes? Whats the 5th tape?
I thought that's what you're supposed to do: (tapecycle >= runspercycle + 1). This will keep the 5th run from writing over the first tape. > Bear in mind that a full backup isn't any one tape, but every tape for > the most recent dumpcycle days will be required to do a full bare > metal recovery. True. I didn't think of that. But this point to what I believe is a weakness of Amanda: Say I have a 1 week dumpcycle, runspercycle = 7. And for simplicity, say I have 7 files: file_0 .. file_6. Also assume that every file is changed everyday so that a level 1 is needed everyday. Also assume that we only do levels 0 and 1. On Sunday, Amanda does a level 0 for file_0, and level 1 for all other files; on Monday, Amanda does a level 0 for file_1, and level 1 for all other files, and so on. At the end of the week, I will have tapes from Sunday through Saturday. Let's call them "tape zero" .. "tape six." Then my customer calls and asks me to restore a file as it was on Wednesday. I can do that easily for file_0, since the level 0 for that file is on "tape zero," backed up on Sunday; and I also have all the necessary level 1's for it. So I grab tape zero (Sunday's level 0) and tape three (Wednesday's level 1), run amrecover, and voila. But if I were to need to recover file_5 "as it was on Wednesday," I would be out of luck. This is because among these 7 tapes, the only level 0 for file_5 is on tape five, backed up on Friday. All level 1's from tape zero through tape 4 for file_5 are useless unless I happen to have preserved the level 0 from the previous cycle. What this means is: unless I preserve tapes from the previous cycle, tapes for one cycle can only guarantee that a file can be restored to its state _sometime_ in that cycle. The more traditional full/incremental backup scheme allows you to, in the case of a 7-day cycle, have the confidence that you can restore a file to its state on any of the last 7 days. But that isn't true with Amanda. :( Regards, Ivan
