SNMP bytes received disagrees with ifconfig
Solution 1:
As twalberg suggests, this is probably a 32-bit overflow problem.
SNMP Interface Counters in are 32-bit (unsigned) by default. If your SNMP daemon and server OS support 64-bit counters they can be found in the ifXtable MIB (.1.3.6.1.2.1.31.1.1)