Re: pg_upgrade and rsync

 On 1/22/15 10:05 PM, Stephen Frost wrote:
In addition, there is a possible race condition in rsync where a file
that is modified in the same second after rsync starts to copy will not
be picked up in a subsequent rsync unless --checksum is used.  This is
fairly easy to prove and is shown here:

https://github.com/pgmasters/backrest/blob/dev/test/lib/BackRestTest/BackupTest.pm#L1667
Right, though that isn't really an issue in this specific case- we're
talking about post-pg_upgrade but before the upgraded cluster has
actually been started, so nothing should be modifying these files.

 Indeed.  This was really directed more at what Bruce said:
I am thinking the fix for standys would be similar to what we recommand
for upgrades with link mode using a rsync-created copy, e.g. use rsync
while the master is running to create a copy of the standby, then shut
down the master and run rsync again.  However, at that point, you might
as well just take a base backup and be done with it.
-- 
- David Steele
david@pgmasters.net