We have tested hw inventory plugin and we are not sure if it is working correctly, because some devices are correctly inventoried but someone not shows all info.
We have observed, when the entPhysicalIndex is grather than > 999 is stopped and not walk more by the next numbers of the OID.
For example for one node, we have:
SNMPv2-SMI::mib-220.127.116.11.18.104.22.1680 = STRING: "WS-X6748-SFP CEF720 48 port 1000mb SFP Rev. 2.5"
but then we have:
SNMPv2-SMI::mib-22.214.171.124.126.96.36.1998 = STRING: "WS-F6700-DFC3C Distributed Forwarding Card 3 Rev. 1.5"
And this part is not showed by hardware inventory.
We think the proble occurs when the dependencies are grather than 1000 but it's only a suggestion.