2017-08-31 18:44 GMT+02:00 Les Mikesell <lesmikes...@gmail.com>: > With rsync xfers, only the changes are going to be transferred. The > difference in a backuppc full and incremental is that the incremental > will use the rsync feature of comparing the timestamp and length of > the files to quickly skip unchanged files, where a full run will do a > full read of all files on the target host for a block checksum > comparison with the old copy. If you use checksum-caching, the > backuppc side will store those on the 2nd full run and not have to > uncompress and compare for the third and subsequent full runs - > however the client side always does a full read so fulls take more > time but not a lot more bandwidth. Bpc3 required the old matching > file to have been in the same location on the same host to avoid > transferring again. Bpc4 is supposed to be able to identify matching > files out of the pool if they have been renamed or you already have a > copy from another host. So if that "new" 5 GB was copied from > somewhere that was already backed up, you would not need to transfer > anything again.
Yes, now it's clear. But my issue is not bandwidth but time. A longer backup will increase load on the host for more time. So, a filled backup is only needed to prevent bit-rot or something similiar, right ? If my filesystem is ZFS, can I safely use a single filled backup for many months? There is no need to compare checksum in bpc, because ZFS already does this. > "Filled" backups don't take a lot more space, just more time to build > the directory structure. If you are concerned about this, keep more > filled copies. In any case the next run will copy in anything > missing. Yes, on the run everyhting missing is synced. But what about a restore? If "file1" was created in the filled backup (now missing) and untouched in the subsequent incremental backup (thus it was not transferred), loosing the filled backup means to loose the "file1" ? ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/
