We have a Sophos XG310 firewall we have been monitoring without issue for well over a year. As of about 3 days ago it has stopped displaying any data for our SNMP traffic sensors on the interfaces, they all read 0.
The NetFlow sensor is working just fine, as are the custom SNMP MiB sensors (CPU, Memory, Disk, etc.)
If I attempt to add a new SNMP Traffic sensor it errors out with the following: "SNMPERR_BAD_ASN1_BUILD (SNMP error # - 11)". I've even attempted adding a new device for the firewall, Auto-Discovery does not install any SNMP traffic sensors for the interfaces.
I'm hoping this isn't a Sophos issue, any help would be greatly appreciated.