Cisco 7821 IP telephone on NetVanta 1638p switch

[des0906]

Here is the essential configuration applied so far with no success.

1) Telephone will not pick up an IP address from the DHCP server.

2) The telephone server and default gateway for the voice VLAN can be pinged from the data switch.

3) When plugged into the port with a PC, an appropriate IP address for the access VLAN is assigned.

4) The Details shown below indicate that the VLAN traffic is being tagged appropriately.

What am I missing? Any assistance would be very much appreciated.

NetVanta 1638P

TELEPHONE PORT

interface gigabit-switchport 0/1

  no shutdown

  switchport access vlan 59

  switchport voice vlan 101

  qos default-cos 1

  qos trust cos

TRUNK PORT

interface gigabit-switchport 0/48

  description UPLINK-TO-2960S

  no shutdown

  switchport mode trunk

  switchport trunk native vlan 255

Cisco 2960S

TRUNK PORT

interface GigabitEthernet1/0/47

switchport trunk native vlan 255

switchport mode trunk

no cdp enable

[des0906]

I managed to get the IP address assigned - I reset the VLAN on the test 2960S and that seems to have worked for some reason. However, it is not getting the TFTP server information from the scope.

[jayh]

It may be that the Cisco phone isn't picking up the LLDP voice VLAN. Check the phone config to see if it supports LLDP. Cisco by default uses CDP. Also make sure that the voice VLAN isn't set manually to something else in the phone.

For the TFTP server, option 66 should have a hostname (and DNS must be working on the phone). Option 150 should be an IP address. You might have to do some experimenting to see what makes the Cisco phone happy.

[Anonymous]

I have a ticket opened with Cisco on this issue for their new 88XX series MPP phones. The phone will boot up fine and obtain an IP from the vvlan after a factory reset, but any subsequent reboots the phone gets Network failure. I did a wireshark for Cisco and found that our Adtran 6355 is passing the vvlan properly through LLDP, but the phone is ignoring it and using the default vlan. This may be similar to what you are experiencing but I am only seeing it on the 88XX MPP firmware. Any 78XX MPP phone doesn't have this issue. I would suggest you grab a wireshark and see what is happening, maybe the phone is ignoring the voice vlan.

[des0906]

I ran the Wireshark per algreat's suggestion - the data was useful to verify the proper information was being provided. I removed and reapplied the VLAN's on the Adtran and did a factory reset on the telephone. The phone now works. I was able to move the Adtran into a light-traffic production area with the telephone for the one permanent user onsite. I also have a Cisco 2602i AP and a camera NVR running off the switch, so everything seems fine.