We are running ESXi 6.5 so my understanding is that vSAN is also version 6.5 which requires multicasting to be enabled on the switch.
We have a single HP 6125g interconnect switch dedicated to the vSAN. If the switch is dedicated to the vSAN is there any need to get into it and adjust multicast settings? My understanding is that without any modifications the switch will treat multicast packets as broadcast packets and this should be fine as the switch is dedicated?
The GA version of 6.5 still required multicast to be anebled, but if you're using 6.5d or later and upgrade the vsan file system it will start using unicast if all hosts are on the same level.
With unicast you will need no special config on your 6125xlg switch, but for multicast you will need to enable igmp snooping.