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New Member

voice problem


I have a problem setting up a VoIP call from a router w/ the following conf

voice-port 2/1/1

input gain 10

connection plar +424

dial-peer voice 50 voip

destination-pattern +424

dtmf-relay cisco-rtp

ip precedence 5

no vad

session target ipv4:

terminating end:

dial-peer voice 777 pots

destination pattern 4T

port 3/0/0

As soon as we get an answer the call is dropped.

Do you have any suggestions of what the reason might be ?

New Member

Re: voice problem

please do some debug in order to check the error

but as a suggestion at the termination end try to put the destination patter +424 coz it is a plar

but i need the debug

it is either debug (AAA or ccapi)



New Member

Re: voice problem

thnks for your response, we made another test and saved the debug herewith attached. We were able to get ring back, but as soon as answered the call is dropped. The originating end goes through a firewall, they have opened ports 1720 and UDP on ports 16384 through 16384 + 4x (based on the fxs ports on the voice card). On some of the previous debug the h245 failed with timeout. I wld appreciate some advice. Thnks

New Member

Re: voice problem


it seems that u are calling someone behind the fire wall which have fake IP right?

it is unlikly to answer coz the firewall will assign a random port to the connection beside the voice port

anyway is it pix firewall?

do u have on it the "fix up protocol"?

pls try to do this : put someone in front of the firewall with real ip and try to call him if everything goes ok then we will know that it is a firewall problem

now if the firewall is pix try to put real ip behind the firewall and without natting (or NAT 0)

and let me know how it goes

please try both 1st -real ip in front of firewall

2nd -real ip behind the firewall

hope this will help



please email me at my hotmail

New Member

Re: voice problem

guys one more thing try this:

Voice calls traversing a PIX Firewall get disconnected

Core Issue The PIX h225 fixup routine is causing the Transmission Control Protocol (TCP) zero byte keepalives between the voice gateway and the Cisco CallManager to fail. Consequently, the voice call gets terminated exactly five minutes after the call setup due to unacknowleged TCP keepalive packets.

Resolution Upgrade to a PIX Firewall version that contains a fix for the problem in Cisco bug ID CSCdy13293.

Another workaround is to downgrade to PIX version 6.1.3 or earlier. You may also disable fixup protocol h323 and h225 if Network Address Translation (NAT) is not used.

New Member

Re: voice problem


thanks for your support, seems to work just fine w/o the firewall. So we just restructured the network design to accomodate that service.