IP Phone dont get IP address from the DHCP Scope

[ciscoccm]

I installed the Windows 2000 Server and the CCM 4.1(3) on a MCS 7800 series, booth of them with the product keys given on Cisco.com. I configured my Cisco voice network on the Cisco Call Manager Administration page. I created a DHCP Scope for IP Phones. When i conect my Cisco IP Phone it displays Configuring IP message on the Screen.
Previously, that IP Phone where conected to other VoIP network and works good.
Why does my Cisco IP Phones do not get IP address on this new Voip network?

 

[pndscm]

Are the phones on the same network as your DHCP server? If not, you'll need to be sure the DHCP request is forwarded across your router. (IP Helper if Cisco router)
Are you sure your not getting an IP address? The phones will display that message even though they get an IP address but they can't get to the TFTP server for the configuration file. Be sure you set up Option 150 in your DHCP scope.

 

[ciscoccm]

Yes, the Cisco IP Phone is in the same network. In fact, i connected a pc on this network and it was automatically assigned an ip of the DHCP Scope that i created for the telephones. My socpe is the next: 20.20.41.40 to 20.20.41.50
My PC got the 20.20.41.41, and my phone just displayed Configuring IP. Then i made a Ping test for rest of the IP in the Scope and no one gave me reply, only my PC.

 

[pndscm]

Get into the network section of the phones config and make sure DHCP is turned on. It depends on the type of phone as to how you access the settings. On a 7940-60 it's like around 30 on the page. If it's turned off, hit **# to unlock the phone and then you should be able to see the softkey. Sorry I can't be more precise but I don't have a phone in front of me right now.

 

[Riktov]

Hi, if you try a static ip address does the phones work?
if so there is a problem with your dhcp server.

Caos is the natural order of things...

 

[ptdog]

One thing you can do a Erase Configuration on the IP Phone. It is option 33 under Network Configuration. You can ensure DHCP is Enabled in here also. Sometimes IP phones still remembers factory ip addresses/settings. This has fixed things for me before.

Next is to check the switchport configuration.

Hope this helps somewhat.

 

[DallasBPF]

you can also do a factory reset..

unplug the phone and after you plug it in hold down the # key until it says the reset configuration comes up, and the sequence is;

123456789*0#

from there it will ask if you want to keep the network settings, say no(option2)

------------------------------------
Dallas, Texas
Telecommunications Tech
CCVP, CCNA, Net+

CCNP in the works

 

[phrk]

Hi, I got another angle on what is happening.
Had a similar situation myself.

Is the Ethernet switch you're plugging into a Cisco?

Assuming it is, is it possible the IOS configuration for the switchport you are using looks something like this?:

interface GigabitEthernet0/5
switchport access vlan 100
switchport mode access
switchport voice vlan 101

If so, when you plug in a regular pc directly to the port and it pulls a dhcp address from the server as desired, it uses "the access vlan." The "access vlan" must have connectivity to the dhcp server in your environment, but you tested that it is happening successfully. The cisco ip phones do a CDP exchange with the Cisco Ethernet switches when they initialize and end up using the "voice vlan" which may not have the required IP connectivity to your dhcp server. Just a guess. hope it helps.

 

[ciscoccm]

Thanks it really works. Thanks for your help