I'm looking at changing the subnets that our RDS instances are currently in.
The subnet group currently has /20
for both a & c zones. I've created new /22
subnets for a & c and associated them for the subnet group, removing the old ones.
I've been running dig
on the rds dns name and the IP that is being returned is still from one of the old /20
subnets.
I'm looking for suggestions on how to resolve this so I can remove the old eni's and subnets.
I've tried toggling the "multi-az" on/off as well as forcefully removing the old (and in use) eni (won't detach).
Short of snapshotting the database and restoring using a new subnet group (i.e. downtime) is there anything else I can do?