On Wed, Dec 21, 2005 at 11:58:05AM -0800, Keith Nicewarner wrote: > I'm new to backups (much less Linux or AMANDA), so forgive me if I'm > missing some basic concepts. > > > .... I think I've resolved the last issue, but here's the > annoying thing: It keeps wanting me to put in a new tape - > even though the previous tape wasn't full or even used. > Is this normal?
OK, basic concepts 101 on tape usage. Amanda only overwrites tapes, it never ever ever appends to the end of a tape it used in an earlier session. So don't even think about running amdump today, sending the data to a tape and then adding tomorrows run to the same tape. Early in a dump run amanda will see if it has a valid tape to use. When it does find one it writes some amanda metadata to the start of the tape (aka the amanda tape header). As far as amanda is concerned, any data that was on that tape before this is gone, even if it doesn't write any backup data to the tape. I.e the tape has been "overwritten", the data is gone. Amanda can also free up the index files and logs for the earlier dump on that tape. Amanda expect you to label and rotate the usage of a number of tapes. The number of tapes is your choice, but a good rule of thumb for the minimum suggested is 1 plus twice the number needed for taping a dumpcycle. I have a dumpcycle of 7 days, 6 runs per dumpcycle and I generally use only one tape per run. So my minimum according to that formula is 1 + 2 * 6, 13 tapes. Remember that is a recommended minimum, I actually rotate 24 tapes. You inform amanda of how often it can reuse tapes with the tapecycle parameter. If you set tapecycle to 5, then it can not reuse the last used tape until 4 other tapes have been used. Tapecycle does not have to match the actual number of tapes in rotation. My tapecycle parameter is 18 though I rotate 24. This lets me gracefully handle (i.e. no action on my part) situations like the occasional dump that needs two tapes to compete or the occasional failed tape. > Since I haven't really gotten a good backup, how can I > start fresh? It won't let me reuse the test tapes. > How can I wipe the tapes clean and make AMANDA think > it's the first day of operation? > To reuse a tape, use amrmtape then relabel it (probably -f option). I once ran a script to refresh a config directory to starting state. But it was a long time ago, so no guarentees. I think it removed the logs, reports, curinfo, and indexes. In my case I keep these in separate directories under the config root so it was easy. Optionally I also I recreated, from previously saved copies, tapelist, amanda.conf, changer.conf, ??? -- Jon H. LaBadie [EMAIL PROTECTED] JG Computing 4455 Province Line Road (609) 252-0159 Princeton, NJ 08540-4322 (609) 683-7220 (fax)
