We are replacing CX600 phones with VVX 311 phone and are running into a problem where the new VVX311 phones sometimes do not accept DHCP offers from our servers. We have switch policy that auto-assigns LLDP-MED and we see the device identified and the correct VLAN tagged on the switch automatically. The old CX600s work flawlessly and the VVX311s only sometimes work. We have moved phones from one port to another, and then replaced them, and cannot find a consistent location-based problem. Phones with the issue would then start working at random points. I found a similar issue with VVX411 listed with Extreme for Enterasys switches, but firmware notes listed the issue as fixed as of 5.3.XX
Out of the box firmware : 5.6.0.17325.
Enterasys Switches: 6.81.10.0001 c5k-series
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