IPsec tunnel between router and PIX, no audio both way!!!

[jolo07310]

We are setting up remote branch through T1 by using IPsec tunnel back to Main site PIX 515E.

CallManager: CCM 4.13

router: c2800nm-advipservicesk9-mz.123-8.T5.bin

PIX: 6.3(4)

I call make a outside call (91xxxxxxxxx) from branch by using T1 PRI at main site.

However, if i call a internal call (4 digits) from branch to main site. I do not have audio (both way).

I call a number (4-digit) inside the branch has no problem.

Any idea??

Thanks

Ken

[anup.anand]

Sounds like an IP routing issue.

Have you verified if there is reachabilily from the IP Phones subnet at the main site to the IP Phones subnet at the remote site?

Does the T1 PRI gateway at main site belong to the same subnet as the IP Phones at the main site?

Regards,

Anup

[jolo07310]

At remote site... I have data vlan and voice vlan.

I plug in my laptop to IP Phone get my data vlan ip address. Then ping from laptop to main site CCM, I have no problem.

T1 PRI gateway is the same subnet as the IP Phones at the main site.

Here is my test:

After call from remote to main OR main to remote... I have no audio both way.

I press "?" twice on the phone, I dont see andy packet at "RxConnt". Then I put either phone "on hold", I got MOH, and "RxConnt" is increasing.

Here is I am thinking, obviously, I have no problem for signaling... once the call got connect, the RTP traffic are between two phones. It seems like there is no RTP once CCM release the call.

Anyone has idea.

Ken

[anup.anand]

You are right. Connectivity between Callmanager and phones is fine, but not between the phones at the remote and main site.

Are you doing any NAT over the VPN?

Try to plug your laptop to the voice VLAN at remote and see if you can ping the phones at the main site.

Regards,

Anup

[jolo07310]

NO NAT through VPN.

For example:

Main site (10.1.0.0/16)

Remote site (10.200.1.0/24)

It will do NAT if remote user surf web.

There is no NAT if the traffic between two sites.

I will do the test next Monday.

Ken