Cannot fetch system description OID .1.3.6.1.2.1.1.1.0

We had also some issues with SNMP, in our case v3 seems to work not proberly.
Downgrading on v2c did the job for the moment - see https://forum.checkmk.com/t/upgrade-to-v2-1-printer-dont-show-any-snmp-informetion/31936/13