Protocol Application Invalid^ A on 7940

[AlfredNketia]

Hi All,

Need your help to resolve "protocol Application Invalid" issue on my Cisco IP phone 7940. I have configured the option 150 on the DHCP server as suggested on some sites but to no avail. Any other means to resolve the "Protocol Application Invalid^ A" issue?

[acampbell]

Hi,

Please look at this document.

I am sure you will the solution in here

http://www.cisco.com/en/US/partner/products/sw/voicesw/ps556/products_tech_note09186a008055c1fe.shtml#solu

HTH

Alex

[AlfredNketia]

Hi Alex,

It is this same document I referenced when I encounted the issue. I have configured the option 150 on the DHCP but to no avail. Do you pls know any alternative way to tackle this?

Thanks.

Alf

[acampbell]

Alf,

The issue is that for some reason the phone is not using (or stpped using ) vlan tagging (802.1Q)

in its packets to the switch.

The phone now needs to attch to a untagged vlan on your data switch.

2 options

1) Changed some port(s) to be access ports but on the voice vlan

2) Remove the voice vlan from the existing port and make sure DHCP opt 150 is available to the data scope.

OPT 1

int fas 0/5

switchport host

switchport access vlan 707

!(VOICE VLAN NUMBER)

OPT 2 -Ammending existing config

int fas 0/7

switchport access vlan 7

switcport voice vlan 707

!

no switchport voice vlan 707

!

If you can get the phone othese ports they should now talk to the DHCP and the CUCM should send the loads etc to sort them out

Once it bis fixed you should be able to return the phones to normal working ports

HTH

Alex