The NetVanta 7100 has limited support for LLDP-MED at this time, but you should be able to see LLDP information for the 1234 at the least (if it is connected to the 7100). Is "no LLDP send-and-receive" enabled for the VLAN interfaces?
The new Polycom software supports LLDP med but the 7100 doesn't show any lldp neighbors.
Is this a limitation?
123X's do show lldp neighbors.
This document elaborates on the LLDP-MED support: https://supportforums.adtran.com/docs/DOC-1640.
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