There is no current lag on the replicas. Replication does traverse a firewall, but we have made no changes recently.
I will say that one of the hot standbys was only recently attached, and it seems like the issues started when we began sending some longer running queries it's way. We have since placed those queries back on the master, but the vacuum issues remain.
One side effect of whatever is happening, is that nightly backups are taking twice as long as normal.
Darron
