Cisco Phone on 3Com 7757

[jainsworth]

I am unable to have Cisco phones placed into a voice vlan on the 3Com 7757 series. I have added the oui information for the phones, have the voice vlan enabled, power etc. all ready to go. The phones work, but they won't place into the voice vlan automatically. Any experience with this problem out there?

Thanks in advance.

 

[ADB100]

Cisco IP Phones use CDP to discover the Voice VLAN, your 3Com switches (?) do not run CDP so this will never work. You can manually configure the Voice VLAN on the IP Phones however this is a bit of an administrative nightmare. Most other vendors support Voice VLAN discovery via DHCP but Cisco don't, obviously Cisco want you to buy Cisco switches.....


Andy

 

[jainsworth]

Andy,

I am aware of most of what you said. Cisco using CDP and not able to use DHCP and so on. However, I did read in one white paper that the 3Com 5500 series has a command called voice vlan legacy. That allows the Cisco phones to work. That is not available in the 7757, so it appears anything automatic is out.

However, I might be forced to do this manually, administrative nightmare or not. What is involved in this from a 3Com perspective?

Thanks in advance.

Joe

 

[ADB100]

Nothing on the 3Com side I think - i.e. you have configured an Access VLAN and a Voice VLAN on each port? With regards to QoS etc I have no idea what can be configured on the 3Com switch so I'm sorry but I can't help you there. On the Cisco IP Phoneyou need to manually enter the 'Admin VLAN' through the settings menu and set this to the Voice VLAN you have configured on the switchports. When in the settings menu you must press the key sequence **#** to be able to edit anything.

HTH

Andy

 

[jainsworth]

Thanks Andy, that did allow me to put the phone into the VLAN I wanted. Is there a way to push that Admin VLAN id out when the phone contacts the TFTP server?

Joe

 

[ADB100]

Not as far as i know.

 

[jainsworth]

Thanks, and FYI, I needed to use **# to unlock the phone, not **#**. I have 7961G series phones.

 

[ADB100]

Thanks, and FYI, I needed to use **# to unlock the phone, not **#**. I have 7961G series phones.

Sorry, **#** reboots the phone. **# unlocks the phone for editing the config.

Andy