Andy, FWIW, I /think/ the replication scheme you are trying to carry out is implemented in Command Prompt's "Mammoth PostgreSQL Replicator" product. From what I understand, their system will independently copy over and replay "TransactionLog" files (translate: WAL files?) on your slave databases in a continuous stream or in a batch. They describe a few other features in their product that might make the commercial option worthwhile to try. CG --- Jeff Frost <jeff@xxxxxxxxxxxxxxxxxxxxxx> wrote: > On Wed, 22 Feb 2006, Andy Shellam wrote: > > > However, if I delete my PG data directory, restore the same base backup > from > > yesterday, and begin recovery, it recovers right up until the last log > file, > > which the previous roll-forward attempt fails. > > The log files were fully archived off the live server to begin with so I > > can't see it's that they've changed or anything. > > > > Is this scenario possible - that you can keep rolling forward over log > files > > as long as necessary, or do you always have to start from a base backup? > > Nothing is changing on the spare, it's literally a sitting duck. > > You must always start with a base backup when you begin the restore otherwise > > the system does not know where to begin the recovery. What I have done in > the > past on a similar system is keep the secondary DB shutdown and make base > backups as often as possible so the recovery time is suitably short when the > secondary is needed. Also a good idea to do test recovers on occassion to > make sure you don't have any corrupt WAL files. If you use rsync, then you > can make the base backup pretty quickly depending on how much of your DB > changes. > > -- > Jeff Frost, Owner <jeff@xxxxxxxxxxxxxxxxxxxxxx> > Frost Consulting, LLC http://www.frostconsultingllc.com/ > Phone: 650-780-7908 FAX: 650-649-1954 > > ---------------------------(end of broadcast)--------------------------- > TIP 9: In versions below 8.0, the planner will ignore your desire to > choose an index scan if your joining column's datatypes do not > match > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
