On Fri, Nov 25, 2016 at 10:05 AM, Patrick B <patrickbakerbr@xxxxxxxxx> wrote: > If I get messages like: > > cp: cannot stat '/walfiles/0000000200001AF8000000A5': No such file or > directory > > In my head, it's saying that it was unable to recover that file and, because > of that, there is missing data. > Even if the server is able to connect to tbe master via streaming > replication, there might be missing data. There might be data that is into > master but not into slave. > > Am I wrong? If so, I don't understand why are the wal_files for, then. In order, a startup process will look for a WAL segments in its local pg_xlog, then using restore_command, and finally via streaming (XLogPageRead in xlog.c). If streaming fails, because for example the segment requested has already been recycled, then startup process switches back to a lookup in archive/pg_xlog. If you happen to have repetitive failures with restore_command, you are missing a segment and the standby would not be able to replay further. If the segment is indeed missing, a new base backup is the way to go. A standby without the WAL segments to replay is useless except if you plan to use PITR and restore to a position before the last segment available in its timeline history. -- Michael -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general