[Pgpool-general] Perform maintenance on secondary without stopping pgpool

[louis fridkis]

In our production system, we are running pgpool 2.2.2. We have two postgres
8.3.3 instances, each on a different host.  We have configured pgpool in
replication mode. We need to shut down the secondary host so we can move it
to a different physical location. We do not want to stop the application
from connecting to pgpool during the time that the secondary is down, or
afterwords. I have indicated that this is not possible, because, if a change
is made to the primary postgres DB while the secondary is down, then, if we
start the secondary and attach it, using pcp_attach_node, the two DBs will
be out-of-sync. The only way to rectify the out-of-sync condition, then,
would be to dump the primary and load it into the secondary. But, this also
would not work, because, if any changes were made, to the primary DB,
between the time the dump was made and the time it was loaded then the two
DBs would still be out-of-sync. My question is: am I correct? Is there any
way to avoid shutting down pgpool in this scenario?

Lou ...
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://pgfoundry.org/pipermail/pgpool-general/attachments/20100726/24aa0df0/attachment.html>