I've got a VRRP interface on a gigabit Ethernet port. SNMP appears to be reporting a default speed for it of 10Mbps.
IF-MIB::ifSpeed.16 = Gauge32: 10000000
Its parent interface shows as
IF-MIB::ifSpeed.3 = Gauge32: 1000000000
There appears to be no way to set this administratively. Needless to say this messes up traffic accounting in most NMS. Should I consider this a bug, and file a report?