Both of the add and edit node wizards are clunky with regard to SNMPv3 credentials.
There are two spots to select credentials (to separate read only and read-write) but there’s no visual clues in the interface that these are separate. I think this should be reworked – a tabbed interface or even some different graphical shading would go a very long way here. I'd also suggest having two test buttons to separate the RO and RW test.
The problems with this web UI was the biggest hold up where when I was adding SNMP to my devices for the first time (new user). Apparently I had set the read-write credentials and Orion was (correctly) failing but the error message was not helpful in isolating the problem at hand. All I needed to do was use the read-only credential drop down to get past that problem. Had the interface (or documentation) been clearer, I probably wouldn't have had to open a support case like I ended up doing.
First screenshot demonstrating the problems with the SNMPv3 credentials interface.
The forum's draft interface is automatically resizing my image, here's an imgur link.
Second screenshot highlighting an issue with insufficient error messages. This error message was ultimately a problem with using read-only credentials in the read-write field. That seems like something simple enough to report a problem with. "Insufficient write privileges" would have been a massive give-away in my case.
