…at least for wireless interfaces:
snmpget from linux machine to MT 2.9.27: (OID = wireless interface tx rate)
management:~# snmpget -v1 -cpublic 10.0.5.1 .1.3.6.1.4.1.14988.1.1.1.1.1.2.3
Error in packet
Reason: (noSuchName) There is no such variable name in this MIB.
Failed object: SNMPv2-SMI::enterprises.14988.1.1.1.1.1.2.3
snmpget from linux machine to same MT downgraded to 2.9.26:(OID = wireless interface tx rate)
management:~# snmpget -v1 -cpublic 10.0.5.1 .1.3.6.1.4.1.14988.1.1.1.1.1.2.3
SNMPv2-SMI::enterprises.14988.1.1.1.1.1.2.3 = Gauge32: 9000000