I know you can set untagged VLAN/PVID for general mode ports using OIDs 22.214.171.124.126.96.36.199.188.8.131.52.4 and 184.108.40.206.220.127.116.11.18.104.22.168.1.3 respectively but we have some devices that for some reason do not play well with general mode and only work properly with access mode on the port. Is there a way to do that via SNMP? I know it's dead simple on cisco switches but I can't find a definitive answer for dell ones
Sorry, I don't have a definitive answer for you. But, since you are able to set general mode, I don't see any reason that access mode would be excluded. Have you tried doing an snmp walk around the ranges of the general mode oid?