On Mon, Jun 4, 2012 at 5:48 PM, Ants Aasma <a...@cybertec.at> wrote: > On Mon, Jun 4, 2012 at 6:20 PM, Fujii Masao <masao.fu...@gmail.com> wrote: >> On Mon, Jun 4, 2012 at 11:25 PM, Ants Aasma <a...@cybertec.at> wrote: >>> On Thu, Sep 29, 2011 at 11:30 PM, Magnus Hagander <mag...@hagander.net> >>> wrote: >>>>> it doesn't say that is not possible to use this for a standby >>>>> server... probably that's why i get the error i put a recovery.conf >>>>> after pg_basebackup finished... maybe we can say that more loudly? >>>> >>>> The idea is, if you use it with -x (or --xlog), it's for taking a >>>> backup/clone, *not* for replication. >>>> >>>> If you use it without -x, then you can use it as the start of a >>>> replica, by adding a recovery.conf. >>>> >>>> But you can't do both at once, that will confuse it. >>> >>> I stumbled upon this again today. There's nothing in the docs that >>> would even hint that using -x shouldn't work to create a replica. Why >>> does it get confused and can we (easily) make it not get confused? At >>> the very least it needs a big fat warning in documentation for the -x >>> option that the resulting backup might not be usable as a standby. >> >> Unless I'm missing something, you can use pg_basebackup -x for the >> standby. If lots of WAL files are generated in the master after >> pg_basebackup -x ends and before you start the standby instance, >> you may get the following error. In this case, you need to consult with >> archived WAL files even though you specified -x option in pg_basebackup. >> >>> FATAL: could not receive data from WAL stream: FATAL: requested WAL >>> segment 00000001000000000000005C has already been removed >> >> Though we have the above problem, pg_basebackup -x is usable for >> the standby, I think. > > I assumed from Magnus's comment that this is a known problem. I wonder > what went wrong if it should have worked. In the case where this > turned up the missing file was an xlog file with the new timeline ID > but one segment before the timeline switch. I'll have to see if I can > create a reproducible case for this.
No, it's more a "there's no reason to do that". I don't think it should necessarily be an actual problem. In your case the missing piece of information is why was there a timeline switch? pg_basebackup shouldn't cause a timeline switch whether you use it in -x mode or not. -- Magnus Hagander Me: http://www.hagander.net/ Work: http://www.redpill-linpro.com/ -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
