Hello, In the Bacula manual I read that :
"However, one must keep in mind that if your Volume Retention period is too short, it may prune the last valid Full backup, and hence until the next Full backup is done, you will not have a complete backup of your system, and in addition, the next Incremental or Differential backup will be promoted to a Full backup. As a consequence, the minimum Volume Retention period should be at twice the interval of your Full backups. This means that if you do a Full backup once a month, the minimum Volume retention period should be two months." I don't understand why the minimum volume retention should be at least twice the interval of the full backups .. ? In my configuration I do a full backup every month with a volume retension period of 45 days, and a daily incremental backup with a volume retension period of 35 days. I don't need archives on a long term, 1 month is enough, but I need to be able to restore a file which has been modified 20 days ago for example (on a daily basis, that's why I make an incremental backup every day). If I follow the Bacula manual, the minimum volume retension should be at least 2 months, but I don't understand why ? In my case, an incremental backup will never be promoted to a full, right ? For example : 1 may 0:00 am : Full backup -> volume "Full-0001" 1 may 8:00 pm : Incremental backup -> volume "Incr-0001" 2 may 8:00 pm : Incremental backup -> volume "Incr-0002" 3 may 8:00 pm : Incremental backup -> volume "Incr-0003" ... 31 may 8:00 pm : Incremental backup -> volume "Incr-0031" 1 june 0:00 am : Full backup -> volume "Full-0002" 1 june 8:00 pm : Incremental backup -> volume "Incr-0032" 2 june 8:00 pm : Incremental backup -> volume "Incr-0033" 3 june 8:00 pm : Incremental backup -> volume "Incr-0034" ... (around 15 june Incr-0001 should be recycled) 1 july 0:00 am : Full backup -> volume "Full-0001" (recycled) etc So in this configuration I will always have a valid Full backup every month and an incremental backup for every day of this month, and I don't see any situation where an incremental backup would be promoted to a full or that my last valid full backup would be pruned.. ?, so why should the minimum volume retention be at least twice the interval of the full backups (60 days in this example) ? Thanks for your answers, Julien -- Julien Cigar Belgian Biodiversity Platform http://www.biodiversity.be Université Libre de Bruxelles (ULB) Campus de la Plaine CP 257 Bâtiment NO, Bureau 4 N4 115C (Niveau 4) Boulevard du Triomphe, entrée ULB 2 B-1050 Bruxelles Mail: [email protected] @biobel: http://biobel.biodiversity.be/person/show/471 Tel : 02 650 57 52 ------------------------------------------------------------------------------ _______________________________________________ Bacula-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/bacula-users
