SIP/2.0 503 Service Unavailable

[Alejandro Perez]

Hi everyone

I configured a SIP Trunk Cisco(10.5)-Avaya and when i make a call i see an error 503 Service Unavailable, this is the Detail:

Detailed Sip Message

SIP/2.0 503 Service Unavailable
Via: SIP/2.0/TLS 172.16.136.13:50392;branch=z9hG4bK1bd58590
From: " ALEX" < sip:8990@172.16.112.13> ;tag=c4729551a75600c273508c1a-271b6e02
To: < sip:3@172.16.112.13> ;tag=834~331f7581-d59e-429e-8808-c6b1e2dc50b6-155792762
Date: Tue, 12 May 2015 21:07:14 GMT
Call-ID: c4729551-a756002b-7d5525e7-69574d4e@172.16.136.13
CSeq: 101 INVITE
Allow-Events: presence
Server: Cisco-CUCM10.5
Reason: Q.850; cause=41
Remote-Party-ID: < sip:3111@172.16.112.13;user=phone> ;party=x-cisco-original-called;privacy=off
Content-Length: 0     

How can i fix it?

[Nadeem Ahmed]

a little details of the issue and from where to where you are calling help us to give some insight on this issue.

from where to where calls failing and getting 503 service unavailable.

CUCM----Avaya or vice versa.

Complete call trace would be also help.

Br,

Nadeem

[Alejandro Perez]

Hi everyone thanks for your help

The problem is when i make the call from Cisco to Avaya, but when the call is from Avaya to Cisco this works fine.

[Marcelo Morais]

Hi Alejandro Perez,

 is there a Firewall between Cisco and Avaya?

Regards.

[Alejandro Perez]

Hi Marcelo

No, there is not a firewall between the servers

Regards

[Nadeem Ahmed]

Hello Alejandro,

Can you please post the CUCM traces.after making one test from Cisco----Avaya which is non-working

Br,

Nadeem

[Alejandro Perez]

Thansk

[Nadeem Ahmed]

Alejandro, The traces are not in detailed. Can you please post complete traces capture in detailed.

also try checking sip_profile what is set to : check it applying TCP+UDP if that works if not send the complete detailed trace.

Br,

Nadeem

[Andrew Bell]

I feel like it may be a simple issue as transport type.  I'd add the session transport type of tcp or udp depending on what Avaya is expecting.  Usually Avaya is TCP.

[Ronak Agarwal]

Hi Alejandro,

Like nadeem mentioned, we would need details to figure out the issue, however, one thing you can check is, the cucm server which is extending the call to avaya should be defined in the avaya as a trusted IP.

Many times, in a multi node CUCM cluster, we only define PUB in the third party server, hoping it would work, however the call is extended by one of the sub and then we receive 503 service unavailable.

Hope it helps!

Regards,

Ronak Agarwal

[Marcelo Morais]

Hi Alejandro Perez,

 beyond what Nadeem Ahmed and Ronak Agarwal already said ... a Cause=41 is Network Failure, check the connection between CUCM and Avaya.

Hope this helps.