Hello momeara, I haven't tested the 1.1.1.8 firmware for this get request. However, I have thoroughly tested the 1.1.2.0 firmware for this specific query and it successfully works.
The best thing I could recommend is to at the minimum use the 1.1.2.0 firmware. The 1.1.1.8 firmware has a known bug with a tcam overflow. This may contribute to the lame behavior.
I can affirm the SNMP V1 and SNMP V2c walk for this OID will work correctly on the 1.1.2.0.
-Tom
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