So I set up a LAGG (LACP) between pfSense and my switch cause I can in my home lab.
pfSense sits on 10.10.10.1 and has 3 1 Gig cables going to the switch on 10.10.10.2
My DNS server sits on 10.10.10.3 and has a single 1 Gig connection to the switch.
Am I correct in thinking that the LAGG is entirely pointless when using a domain? If I am wrong, how come?
Not sure what you mean. LAGG is a fine setup if you can do it and doesn’t make anything overkill or pointless. Maybe elaborate on why you think its point for a domain.
There isn’t a relationship or dependency between LACP and running a domain. LACP is strictly a network service and doesn’t know anything about the type of traffic a system is running across it.
The reason why I think it would be a bottle neck is cause if I enter “mediaserver.local” all the traffic would pass though the DNS making the LAGG capped at 1 Gig rather than 3 Gig.
A LAGG setup with three 1Gb links won’t get you 3Gb throughput across them. Any given flow will only go across one link and this is all based on the hashing algorithm configuration.