Cisco ipphone 8845 connected to 3Com Switch 4500G 48-Port

[alejandrortiz]

I have a cisco ip phone 8845 connected to port in switch 3com, but the cisco doesn't take ip from DHCP server.

The port configuration in the 3com is:

interface GigabitEthernet1/0/18
port link-type trunk
port trunk permit vlan 1 400 403 to 404
port trunk pvid vlan 400
broadcast-suppression pps 3000
undo jumboframe enable
stp edged-port enable

The vlan 403 is the voice vlan.

When I connect a cisco 7821 phone to the same port it register in the CUCM.

I want to know if I have to do something aditional to cisco 8845.

[Brandon Buffin]

Can you try to manually set the admin VLAN on the phone to the voice VLAN?

Brandon

[alejandrortiz]

Yes, the admin vlan I set in 403 and the PC vlan in 400. 

[sethainsley]

Hi Alejandrortiz,

Due to your explanation, since we will use a non-Cisco switch (not CDP capable) we need to explicitly define the Voice VLAN on the Cisco phone.

Could you please confirm that both the 7821 phone and the 8845 phone have the VLAN manually specified in the network settings as VLAN 403?

(I see Brandon asked the same/a similar question but I just want to verify that currently both phones are configured with same VLAN, then lets proceed from there)

Thanks!

Seth

[alejandrortiz]

Hi Seth, in both phones I set the admin VLAN 403 and the PC VLAN 400. The 7821 works fine, but the 8845 doesn't take ip from dhcp vlan 403 even connect the phones in the same port, it takes ip address from the pool of vlan 400 and ask for activation code or domain.

[sethainsley]

Hi Alejandrortiz,

Please try setting the 'Operational VLAN ID' on the 8845 to VLAN 403 and let me know if this helps.

Thanks!

Seth

[alejandrortiz]

Hi Seth,

The operational vlan can't be changed, this option is disable, only admin vlan.

I verify this config in the 7821, but the operational vlan is activated when the phone is up, nor can configure.

[sethainsley]

Hi Alejandrortiz,

Interesting, Can you please remove the PC VLAN and change the Admin VLAN to 403, then apply?

Your PC should naturally go on VLAN 400 anyway since your switch config appears to tag untagged traffic on the port with VLAN 400 and the phone will just passthrough the traffic.

Let me know if this works.

Cheers!

Seth

[alejandrortiz]

At the end, we have to let the phone with PC DHCP and we change TFTP server ip address. They are working this way.

Thanks for your help.