Configuring Avaya IP telephony (options 176 and 242)

Avaya IP telephones use site-specific options 176 and 242 as a method to obtain parameters from the DHCP server.

On receipt of a discovery packet from the Avaya IP telephone client, a DHCP offer message must be sent back. Options 176 and 242 must be added with the details of IP telephony voice and data servers present in the network, along with mandatory options.

Option 176 is used for voice server representation.
Option 242 is used for data servers.

NOTE

Options 176 and 242 are ignored for non-Avaya IP telephone clients.

Enter global configuration mode.
```
device# configure terminal
```
Configure an address pool in the DHCP server and enter DHCP server pool configuration mode.
```
device(config)# ip dhcp-server pool cabo
```
Enter the ip-telephony data command followed by the supported parameters. The parameters you can add for IP telephony data are mcipadd, mcport, httpsrvr, l2qaud, l2qsig, l2qvlan, tftpsrvr, tlssrvr, and vlantest.
The following example specifies the MCIP address and MCPORT of the data server.
```
device(config-dhcp-cabo)# ip-telephony data mcipadd 1.1.1.2 mcport 1719
```
Enter the ip-telephony voice command followed by the supported parameters. The parameters you can add for IP telephony voice are mcipadd, mcport, httpsrvr, l2qaud, l2qsig, l2qvlan, tftpsrvr, tlssrvr, and vlantest.
The following example specifies the MCIP address and MCPORT of the voice server.
```
device(config-dhcp-cabo)# ip-telephony voice mcipadd 1.1.1.2 mcport 1719
```
Deploy the DHCP address pool.

Enter the show ip dhcp-server address-pools command to verify the configured IP telephony options.

device(config)# show ip dhcp-server address-pools 

Showing all address pool(s):
                    Pool Name:  test
 Time elapsed since last save:  00d:00h:01m:21s
Total number of active leases:  1
           Address Pool State:  active
      Pool Configured Options:
                        lease:  1 0 0
ip-telephony-voice-server: MCIPADD=192.168.42.1,MCPORT=1719,TFTPSRVR=192.168.42.1
ip-telephony-data-server: MCIPADD=192.168.42.1,MCPORT=1719,TFTPSRVR=192.168.42.1
                      network:  50.50.50.0 255.255.255.0

Contents

Configuring Avaya IP telephony (options 176 and 242)