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New Member

IP Phone over VPN Tunnel

I have read some of the issues on this post, but have not found a solution to my problem.

I have a centralised CCM3.3.2, and VPN tunnel to a remote site, using checkpoint firewalls.

On the central site, the CCM is acting as a DHCP server with option 150.

The IP Phone at the remote site, is getting the correct IP address/Mask, TFTP server address, but failing to get the CCM IP address. In the CCM 1 field it shows CiscoCM1, which is not the name of any of my CCM Servers.

As a result, the phone is not registering with the CCM. Any ideas will really be appreciated. Thanks

7 REPLIES
New Member

Re: IP Phone over VPN Tunnel

Hi,

You may want to reset the phone back to factory defaults, since it may still want to register with perhaps an old CM server that it previously was configured with. Also, if that phone was somehow upgraded with a new load, and your current server has an older phone load, it may not register at all.

New Member

Re: IP Phone over VPN Tunnel

I have done that already, and the phone does not have a new load. Thanks for the suggestion

Re: IP Phone over VPN Tunnel

Are you using NAT or PAT on the Tunnel? How many clients on the remote side? Are other clients using the same DHCP server or a different server?

New Member

Re: IP Phone over VPN Tunnel

CiscoCM1 is the default call manger name an ip phone will register to if it cant find the call manager. are you able to reach the call manger ip address\name from the vlan that the phones are on?

New Member

Re: IP Phone over VPN Tunnel

Are you sure that the Checkpoint firewalls are allowing the TFTP transfer? Have you tried using a PC at the remote site with some sort of a TFTP client to see if TFTP works -- put a PC into the "phone subnet" and try to TFTP to your call manager (or whatever IP address is listed in the option 150 setting)?

John

New Member

Re: IP Phone over VPN Tunnel

I am using NAT in the tunnel. Other clients are using the same DHCP server. I am able to ping the IP address on the phone from CCM, and able to reach the CCM IP address...from the voice vlan

The FW ia allowing all traffic right now

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