There's one last thing we need to cover before ending this chapter. If a server is causing problems, there's a good chance that the infrastructure department will want to reclaim, rebuild, or replace it. Simply stopping the broken server is a possible solution, but there is a safer way to decouple DRBD from another system.
In this recipe, we'll quickly cover partially dismantling a running DRBD system without disrupting the active server.
By now, we need the full stack and probably a fully active database server as well. Follow all the recipes up to Tweaking XFS performance before starting here.
For this recipe, we will need two PostgreSQL servers: pg1 and pg2, where pg1 is the currently active node. Follow these steps as the root user on the system indicated to permanently remove pg2 from the DRBD cluster:
Execute this command on both
pg1andpg2to disconnect DRBD:drbdadm disconnect pgInvalidate the data on the remote node with
drbdadm...