For a beta site we just installed 2 SG300-52's and the OnPlus Portal keeps telling me that the credentials were not valid when last tried. We have an SG300-10P here and we get the same results. Any thoughts? I've even tried typing the username & password in notepad, then testing them by copying/pasting them into the Web GUI for the SG's and they work fine but when I copy/paste them into OnPlus they continue to say they're not valid. I have Bonjour and CDP enabled on all the SGs.
The SG300 driver has a few different credentials inputs that are possible they are documented in the user guide under the SG300.
The basics are if you have SNMP enabled on the switch the driver will use SNMP v2 or v3 credentials. If you don’t have SNMP enabled you should be fine with the http credentials.