Hi Tomas, Thanks. Increasing the wal_keep_segments to 4000 did the trick.
I will set up WAL archive as well. Thanks again. Ashish. On Sat, Nov 19, 2011 at 5:59 PM, Tomas Vondra <t...@fuzzy.cz> wrote: > Hi, > > On 19 Listopad 2011, 10:44, Ashish Gupta wrote: > > I searched on various forums, where people encountered similar error, > > however in all such issues WAL file existed on Master. In this case > Master > > is not retaining the WAL file required by the Slave. > > > > I am unable to understand as to why Master is not retaining the WAL > files. > > Any pointer/suggestions would be helpful. > > Thanks for attention. > > The cause is very simple - the standby needs all WAL segments created > since the backup started, but the master removes some of them. There are > two ways to fix this: > > 1) increase the wal_keep_segments so that enough segments is kept > > It seems that the slave asked for B110000000D when master already created > B110000000D. That's almost 4000 segments if I'm counting correctly. That > means your database is either quite busy or the backup takes very long > time. > > This stores all the data on master, so you'll have to keep that in mind > when planning the capacity. For example the 4000 segments are almost 64GB. > > 2) Set up a WAL archive - a separate instance where the WAL segments are > kept. See how the archive_command works. And there's pg_archivecleanup for > maintenance of the archive. > > Tomas > >
