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NEC ip phone with cisco 3650 POE


Can some one help me please ?


I have NEC ip phones that i need to move them from HP to cisco switches.


I have created two vlans , one for the data and one for the voice . the problem is when i connect the phone to the port, it get an ip from the data vlan .


I've tried many things but i could not get the problem solved, i have tried the following 

1- interface GigabitEthernet0/12
    switchport voice vlan 2
    spanning-tree portfast

2- interface GigabitEthernet0/12
    switchport trunk encapsulation dot1q
    switchport mode trunk

 Change from CDL to LLDP


Nothing seems to be work


with everything i tried, the phone keep getting ip from the data vlan not the voice.


Both DHCP scopes are configured on the switch (for testing)




Community Member

Hi Khaled,I have a same

Hi Khaled,

I have a same problem now. if you solved this problem, would you tell me how you solved?

I use access vlan istedad of voice vlan as workaround now.


Community Member

Hi Mitsou,If the phones have

Hi Mitsou,

If the phones have been registered in a previous setup it will not pick a new ip , you have to delete the configs on the phones flash and reconnect them again to the switch.

I hope this help.



Community Member

Hi Khaled,Thank you for your

Hi Khaled,

Thank you for your kindly reply.

at that time, did you use access VLAN or voice VLAN?


Community Member

Hi,Voice vlan and LLDP enable


Voice vlan and LLDP enable .


Hope this help


Community Member

would you tell me how did you

would you tell me how did you use voice VLAN?

in my case, I configured PoE switch below, but voice VLAN didnn't work...


interface GigabitEthernet0/2
switchport voice vlan 518


but IP phone works when I set "access vlan 518"...

I couldn't understand because I couldn't set voice vlan in IP Phone...

Community Member

on the global config mode sw1

on the global config mode 

sw1(config)# lldp run

NEC phone don't understand cdp so the switch will not found a phone unless you enable the lldp .

after that you can check if the phone has been detected by issuing 

# show lldp neighbour

now it it should work with voice vlan command



Community Member

I will try it! thank you so

I will try it! thank you so much



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