one way voice PSTN calls via H.323

[Mohd. Hidzwan Tamrin]

Hi,

I have two CUCM running, one is version5 other is version8.6..By using the same voicegateway (H.323), phones registered to new CUCM unable to communicate both way while in PSTN call. From outside we can hear voice, but from ip phone we heard nothing not even a ringing tone. No issue with internal calls.

VG ip address : 192.168.2.6

old CM : 192.168.2.11 & 12

new CUCM : 192.168.2.21

phone ip address : 10.23.21.0/24

I tried put my ip phone in the same segment as the gateway, the PSTN call works fine.

my dial peer config as per below;

!

dial-peer voice 100 voip

description ***Connection to CCM-PUB***

destination-pattern .T

progress_ind setup enable 3

session target ipv4:192.168.2.11

dtmf-relay h245-alphanumeric

codec g711ulaw

no vad

!

dial-peer voice 101 voip

description ***Connection to CCM-SEC***

destination-pattern .T

progress_ind setup enable 3

session target ipv4:192.168.2.12

dtmf-relay h245-alphanumeric

codec g711ulaw

no vad

!

!

dial-peer voice 102 voip

description ***Connection to CCM8-PUB***

destination-pattern .T

progress_ind setup enable 3

session target ipv4:192.168.2.21

dtmf-relay h245-alphanumeric

codec g711ulaw

no vad

!

[Chris Deren · Accepted solution]

One way audio is 99% of times related to routing issues, couple of things to check:

1. ensure you have ip routing enabled on the router/GW
2. ensure your H323 protocol is bound to an interface via:

interface X/X

h323-gateway voip interface

h323-gateway voip bind srcaddr x.x.x.x

HTH,

Chris

[Mohd. Hidzwan Tamrin]

This is our VG current config;

!

interface GigabitEthernet0/0

ip address 192.168.2.6 255.255.255.0

duplex full

speed 1000

no negotiation auto

h323-gateway voip interface

h323-gateway voip bind srcaddr 192.168.2.6

!

any phones that still registered to old CM had no issue with both communication, only phones that had migrate to new CUCM experience this.

[Mohd. Hidzwan Tamrin]

Problem solved, add routing to allow reachability from VG to voice vlans.

[Chris Deren]

As I said one way audio is caused by ip routing issue 99% of the time.

Please rate all useful posts!

Chris

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