Re: What will happen if I start Archive before cancelling Logical Log.

In article <3A7BD0F4.C3FBD1A0@hotmail.com>, Brett Randall <brett_s_rREMOVECAPITALS@hotmail.com> wrote: > > Murat YILDIZ wrote: > > > > What will happen if I start a Level 0 Archive on a DLT while Logical > > log continues on another tape device ( DDS)?Thanks... > > > > Sent via Deja.com > > http://www.deja.com/ > > I assume that by Logical Log that you have ontape -c running. > > What will happen - your Logical Logs will continue to be backed up as > they are filled on on tape, and you will get a zero level archive on the > DLT. > > Archives and log-backups can occur simultaneously on IDS. Yes I have ontape -c on DDS and ontape -s on DLT.But if we consider recovery, will it be still ok to recover till the last backed Logical log?Could anyone explain how the Archive and Logical log recovery is performed?(Expecially with logical log recovery) > > Brett Randall > Sent via Deja.com http://www.deja.com/

Murat YILDIZ wrote: > > In article <3A7BD0F4.C3FBD1A0@hotmail.com>, > Brett Randall <brett_s_rREMOVECAPITALS@hotmail.com> wrote: > > > > Murat YILDIZ wrote: > > > > > > What will happen if I start a Level 0 Archive on a DLT while Logical > > > log continues on another tape device ( DDS)?Thanks... > > > > > > Sent via Deja.com > > > http://www.deja.com/ > > > > I assume that by Logical Log that you have ontape -c running. > > > > What will happen - your Logical Logs will continue to be backed up as > > they are filled on on tape, and you will get a zero level archive on > the > > DLT. > > > > Archives and log-backups can occur simultaneously on IDS. > > Yes I have ontape -c on DDS and ontape -s on DLT.But if we consider > recovery, will it be still ok to recover till the last backed Logical > log?Could anyone explain how the Archive and Logical log recovery is > performed?(Expecially with logical log recovery) You really will need to RTFM "Archive and Backup Guide". Until you read and understand this yourself, how can you be sure that you know what/how to recover? You need to practice your recovery. That said, I will share my limited understanding with you. 1) A zero level archive will always provide physical and logical consistency, at the point when the archive starts. This is possible because the archive writes all pages to disk as they were at the "archive checkpoint", and it also writes out the current logical logs, so "open transactions" at the time of the archive checkpoint can be rolled back. 2) To get full recovery (including logical logs backup up to tape during the archive), ontape will offer to restore logical logs once a restore is completed. You need not worry about logs that were "being backed up" before, during, or after the archive. Log files are uniquely numbered and the engine will start log-replay from the first log after the log saved in the archive. This log number is listed on STDOUT and in the online message log. So, if your log tape contains logs 1001-1234 and your archive contained log 1100, the log-replay will skip the first 100 logs on the tape, as these are covered by the archive. 3) Smart DBAs keep track of the logical log numbers that are contained on both archive tapes and logical log tapes, so that recovery is smooth (no "is this the right tape ...?"). ___Practice Your Recovery!___ HTH Brett Randall

When an archive is started, there is a checkpoint that is taken. That checkpoint is the archive snapshop point. The archive will take a backup of the pages as they are at that point in time. If a page is altered that has not been backed up then the before image of that page is placed on the archive, not the after image. When logical recover is appled to an archive, the recovery process begins at that checkpoint and works it's way forward in time. Murat YILDIZ wrote: > In article <3A7BD0F4.C3FBD1A0@hotmail.com>, > Brett Randall <brett_s_rREMOVECAPITALS@hotmail.com> wrote: > > > > Murat YILDIZ wrote: > > > > > > What will happen if I start a Level 0 Archive on a DLT while Logical > > > log continues on another tape device ( DDS)?Thanks... > > > > > > Sent via Deja.com > > > http://www.deja.com/ > > > > I assume that by Logical Log that you have ontape -c running. > > > > What will happen - your Logical Logs will continue to be backed up as > > they are filled on on tape, and you will get a zero level archive on > the > > DLT. > > > > Archives and log-backups can occur simultaneously on IDS. > > Yes I have ontape -c on DDS and ontape -s on DLT.But if we consider > recovery, will it be still ok to recover till the last backed Logical > log?Could anyone explain how the Archive and Logical log recovery is > performed?(Expecially with logical log recovery) > > > > > Brett Randall > > > > Sent via Deja.com > http://www.deja.com/