Just been looking at a HA pair system where the interface groups (VIFs) on each controller have different names and I want to enable ndmpd.preferred_interface on the controllers.
When running options ndmpd.preferred_interface <interface name> the following warning message is displayed:
You are changing option ndmpd.preferred_interface which applies to both members of
the HA configuration in takeover mode.
This value must be the same in both HA members prior to any takeover
or giveback, or that next takeover/giveback may not work correctly.
Does anyone have any knowledge of what will actually happen during CF failover if the ndmpd.preferred_interface value is different on each node?
In this case the ifgrp on controller A is "ifgrpA" and on controller B it is "ifgrpB". The partnert interface names are configure correctly in ifconfig (ifgrpA's partner is ifgrpB and vice versa) but this is a different issue. I will probably need to change the ifgrp names anyway but I would like some idea of the risk before proceeding.
I have to test on a live system but the option should be assumed by the failed node on takeover. So if nodeA ha ifgrpA preferred and nodeB has IfgrpB preferred then on takeover of b by a then b in failover node will use ifgrpA which doesn't exist in b. although not sure if it would work if a is the partner interface. Good question and need to test to confirm what happens.