Martin Simmons wrote: >> 23-Nov 22:06 gershwin-sd JobId 506: Error: Re-read of last block OK, but >> block numbers differ. Last block=4963 Current block=4963. >> 23-Nov 22:06 gershwin-sd JobId 506: End of medium on Volume >> "MainCatalog-004" Bytes=28,148,843,520 Blocks=436,334 at 23-Nov-2008 22:06. >> However: I also think that that catalog backup has actually been >> corrupted, because I think the SD would write the data from block >> 4963 at the beginning of the new tape, which means if I restored >> that particular backup, I would find a block of data repeated. > I would expect it to be OK, as long as the catalog says that block 4963 is on > the second tape.
Thank for the reply; I am still not sure this is OK, though. Since my original post, I have done a bit of research, and it looks like some drives actually behave this way. [ The block numbers refer to the physical position on the tape, BTW, rather than being a sequence count within the backup data stream, so the first block on the next tape will be block 0. I cannot use that to determine whether the data has been written twice. ] Apparently, some drives will write until they run out of tape, then they fail the write and return EOM. However, some drives will detect *impending* end of tape, and start giving you EOM a little bit before the physical end of the tape, but they will still successfully write data. > Have you tried the btape fill test? That should check Bacula's logic for this > case. I admit I cannot now remember if I exhaustively tested this drive; I was concentrating mainly on the DLT I use for the main backups. I'll dig out a couple of blank tapes and test it though. I will also get that catalog backup off the tape, and have a close look at the SQL file I get back, in case there is a duplicated block of data. I may move over to the devel list, actually, depending on how the tests work out, just in case there is a (silent) problem with some drives. If there is, however, the SD can easily detect the behaviour of the drive, because it gets the block number back when it re-reads the last block on the tape. Allan ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
