Thread: Logical replication DNS cache
I've got a server at example.com that currently publishes logical replication to a server in AWS RDS. I plan to move the server at example.com so that it has a new IP address (but same domain name).
I'm curious if anybody knows how the logical replication subscriber in AWS would handle that.
There's at least three layers where the DNS might be cached, creating breakage once the move is complete:
- Postgres itself
- AWS's postgresql fork in RDS might have something
- The OS underlying amazon's RDS service
I expect this is a tough question unless somebody has done this before, but any ideas on how postgresql would handle this kind of thing? Or is there a way to flush the DNS cache that postgresql (or RDS or the OS) has?
I'm just beginning to explore this, but if anybody has experience, I'd love to hear it.
Thanks,
Mike
On 2019-12-12 01:37, Mike Lissner wrote: > I've got a server at example.com <http://example.com> that currently > publishes logical replication to a server in AWS RDS. I plan to move the > server at example.com <http://example.com> so that it has a new IP > address (but same domain name). > > I'm curious if anybody knows how the logical replication subscriber in > AWS would handle that. > > There's at least three layers where the DNS might be cached, creating > breakage once the move is complete: > > - Postgres itself > > - AWS's postgresql fork in RDS might have something > > - The OS underlying amazon's RDS service Postgres itself doesn't cache any host name resolution results. I don't know about the other two pieces. -- Peter Eisentraut http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services