Hey Drew, Correct. This will all depend on what sort of backup system you are after. If you want to recover up to its existing state, you will need a script that will nab the current log, located in the x_log dir, and backup this up every x minutes. Along with this you will be backing up your WAL's. You can add the current X log to the WAL and recover your DB to its existing state. On Thu, 28 Aug 2008 05:24:56 -0700 (PDT), windsurferdrew-pg@xxxxxxxxx wrote: > Thanks Steve. > > If I understand your comment regarding the 16MB limit, it means I should > not worry about the WAL file not being copied to the archive directory. > > > I hope this also means a subsequent attempt to restore the db will > successfully work since the WAL file is still in the pg_xlog directory. > > Drew > > > ----- Original Message ---- > From: "steve@xxxxxxxxxxxxxxxxxx" <steve@xxxxxxxxxxxxxxxxxx> > To: windsurferdrew-pg@xxxxxxxxx > Cc: pgsql-admin@xxxxxxxxxxxxxx > Sent: Wednesday, August 27, 2008 5:31:30 PM > Subject: Re: [ADMIN] WAL files during a backup > > This WAL wont get copied to the archive directory until it reaches 16MB > worth of transactional data. I will actually be testing today for work, if > I can grab the latest xlog and this can be used in the restore aswell as > archived WAL's > > I will let you know the results, unless some1 else already knows.? > > On Wed, 27 Aug 2008 13:49:13 -0700 (PDT), windsurferdrew-pg@xxxxxxxxx > wrote: >> Steve, thanks for your response and your question. >> >> Ok, here is some clarification on the WAL file name used in the example >> below. >> >> The WAL file name I used in the example is actually >> 000000010000000000000088, and the backup file name is >> 000000010000000000000088.0089ED8C.backup. >> >> The WAL file 000000010000000000000088 exists in the data/pg_xlog > directory >> after the backup run is completed. The problem for me is that it wasn't >> copied to the archive directory. >> >> >> Since this is a test machine and not much db activity occurring on this >> server, there have been 6 additional WAL files added to the pg_xlog >> directory in the last 6 hours since the last backup was performed. >> >> Drew >> >> >> ----- Original Message ---- >> From: "steve@xxxxxxxxxxxxxxxxxx" <steve@xxxxxxxxxxxxxxxxxx> >> To: windsurferdrew-pg@xxxxxxxxx >> Cc: pgsql-admin@xxxxxxxxxxxxxx >> Sent: Wednesday, August 27, 2008 4:36:24 PM >> Subject: Re: [ADMIN] WAL files during a backup >> >> 00000001000000000000223387 would usually be the next WAL to be written. >> How often are you WALs written out? >> >> On Wed, 27 Aug 2008 07:07:17 -0700 (PDT), windsurferdrew-pg@xxxxxxxxx >> wrote: >>> I have a question regarding the WAL files that are moved during a > backup >> to >>> the "archive directory". >>> >>> I have setup the postgresql.conf file to have the following archive >>> command: >>> >>> archive_command = 'cp -i %p /var/lib/pgsql/backups/%f </dev/null' >>> >>> Environment: >>> PG Version 8.1.4 >>> OS: Linux 2.6.18-8.el5 >>> >>> After I have run the pg_hotbackup script, the backups directory > contains >>> only 2 files: >>> 1. The gzipped tar file pg_hotbackup_<timestamp>.tar.gz, and >>> 2. a WAL file ".backup" file, (for example >>> 00000001000000000000223387.0089ED8C.backup) >>> >>> The actual WAL file did not get copied to the backups directory. From >> the >>> example above, I would have expected at least 1 WAL file named >>> 00000001000000000000223387 to be in the backups directory. >>> >>> My questions are: >>> 1. Is this normal behavior? (perhaps no activity in the DB to cause a >> WAL >>> file write during the backup?) >>> 2. If I try to restore the DB without this WAL file, will the restore >>> fail? >>> >>> Thanks in advance >>> >>> Drew >>> >>> >>> > > >
