Cisco VOIP to Avaya. Options 242, 176 etc? Phones are staying in Data Vlan and not going over to Voice Vlan.

Davide Minetti
Davide Minetti used Ask the Experts™
Could someone please help me understand what needs to be done transitioning from Cisco VOIP to Avaya?  Specifically, Option 242 that needs to be configured on DHCP Voice Pool? The client claims that the phones are staying in Data Vlan (Vlan 1) and not going over to Voice Vlan (Vlan 900).

The setup is pretty straight forward. There is one building (3 closets total) and only 2 Vlans: Data and Voice.  

Vlan 1 Data
Vlan 900 Voice

The Cisco 2921 Router is configured for Voice DHCP like this:
ip dhcp pool VOIP
 option 150 ip
 dns-server is the Call Manager IP.

I believe there is an Avaya server (controller) onsite that will be acting as DHCP for the new Avaya phones.

What needs to be done for the Avaya phones to obtain 10.13.x.x IP addresses and not 10.12.x.x ? I've read about Options 242 (or 176) that need to be configured but I'm not sure how to go about it. I haven't really worked with Avaya phones before.

What about LLDP? The switches are Cisco, 2960x. Switchport are configured to access vlan 1 and Voice vlan 900.

Any help would be appreciated!
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kevinhsiehNetwork Engineer

Yes, you need LLDP enabled on the switches. You also need to set the DHCP options for your phones. Which option you need depends on the model phones you have. I believe I have option 176 and 242 set on my network using Microsoft DHCP. There are many parameters that can be set. I suggest reviewing the Avaya documentation for your phones.
LLDP is nice to have, but not required

A Full DHCP option 242 would look something like


MCIPADD is the address(es) of the call server(s)
MCPORT is the port used on the call server
HTTPSRVR is the address of the web server used for the 46xxsettings and can also hold backups of phones and new firmware
HTTPDIR is the directory on the webserver
L2Q is for setting whether VLAN tagging should be used
L2QVLAN is the tagged VLAN to use

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