snmp-server user v3user v3group v3 auth md5 v3user123
But there are certainly other options you can use.
However, some devices have a bug where they use a non-unique engine ID. DFM requires that every device have a unique SNMP engine ID. Use "show snmp engineID" on your devices and make sure the IDs are unique across all of them. Use the "snmp-server engineID" command to set a unique value if you find any duplicates. Then delete and re-add the devices in DFM and they should become managed.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...