Solved: No incomming calls on SIP trunk after inactivity

m.junghage · ‎04-09-2010

Hi,

A client switched to SIP telephony on thier UC520. The first day everything worked fine, the second day incoming call's did'nt come through. After a reload the trunks became registered again and calls started coming in. After thier lunchbreak (when the phones had'nt been used for a while) Incoming call's once again failed until someone made a outgoing call.

The SIP services provider claims the UC is'nt recieving the packages sent and that they are probably dropped by the internal firewall.

The UC:s wan interface is connected to a public ip with nothing in the way and the SIP trunk is configured using the CCA. I've lowered the firewall to "low" setting.

I've configured several UC:s with this sp before but not with the latest software release and CCA 2.2.2 so I wonder if there's some change in what CCA does to the access-lists after a trunk is configured?

Any help or ideas are greatly appreciated.

Best regards.

Alberto Montilla · ‎04-09-2010

Dear Markus;

Potentially customer UC500 is deployed under a NAT router (please confirm). What is probably happening is that router is closing the SIP UDP ports after some inactivity time (15-30 sec in most of routers) so incoming SIP messages cannot pass in anylonger.

Check the router (I suspect it is not a Cisco one - No ALG), and create call forward rules for the SIP ports towards UC500.

Hope this helps.

Alberto

View solution in original post

Maulik Shah · ‎04-09-2010

RJ - take a look at the link below to see if it gives you any pointers:

https://supportforums.cisco.com/docs/DOC-9832

Markus - can you gather a log and post back on the community for when calls fail inbound along with a configuration (Pvt Msg me if you do not want share config on community) - check doc below for how to gather logs:

https://supportforums.cisco.com/docs/DOC-9824

- Also, does this work if you make an outbound call first and then make an inbound call?

- Do the SIP registrations stay up all the time per below:

https://supportforums.cisco.com/docs/DOC-9830

View solution in original post

Alberto Montilla · ‎04-09-2010

Dear Markus;

Potentially customer UC500 is deployed under a NAT router (please confirm). What is probably happening is that router is closing the SIP UDP ports after some inactivity time (15-30 sec in most of routers) so incoming SIP messages cannot pass in anylonger.

Check the router (I suspect it is not a Cisco one - No ALG), and create call forward rules for the SIP ports towards UC500.

Hope this helps.

Alberto

m.junghage · ‎04-09-2010

Hi Alberto,

The UC is connected directly to the ISP with no router attached in front of it and it has a static public IP. So that leaves me with the UC firewall and if maybe the ISP is interfering with the packets.

rjmiller8490 · ‎04-09-2010

Have you recently update IOS? I have lost all incoming since upgrading to SBCS 8.0.1. Outgoing good, registration good, etc. I have just about got to the point of calling TAC... gotta be desperate to go into that goose chase but almost there. If anyone has any ideas please let me know. Otherwise when TAC solves it... painful process but they always do... I will post the solution.

RJ

Maulik Shah · ‎04-09-2010

RJ - take a look at the link below to see if it gives you any pointers:

https://supportforums.cisco.com/docs/DOC-9832

Markus - can you gather a log and post back on the community for when calls fail inbound along with a configuration (Pvt Msg me if you do not want share config on community) - check doc below for how to gather logs:

https://supportforums.cisco.com/docs/DOC-9824

- Also, does this work if you make an outbound call first and then make an inbound call?

- Do the SIP registrations stay up all the time per below:

https://supportforums.cisco.com/docs/DOC-9830

m.junghage · ‎04-09-2010

RJ: I did upgrade the box to the latest software pack before any configuration was made. As I have done with two other UC:s the last week. All of them uses the same SIP SP, IOS and Software pack release. And since you don't even get any calls in I don't think we have the same problem.

I do agree though that calling the TAC can be a bit of a hasle, since I'm located in europe my cases always get's routed to Jordan and the language barrier can be a bit steep :). The US TAC is much easier dealing with.

m.junghage · ‎04-09-2010

Hi Maulik,

Thank you for taking time to help me.

I will collect debugs tomorrow morning and post them.

- Yes, outgoing calls keeps the sip registrar up and incomming calls are once again allowed in.

- No, after inactivity the registrar goes down. At least in the cases I've been able to see.

m.junghage · ‎04-15-2010

This issue was resolved after the sip serviceprovider lowered the option ping to 60 seconds. The funny thing is that we've used the same provider with a couple of UC's before and have not seen the same problem.

Steven DiStefano · ‎04-15-2010

Markus,

Glad to hear. Can you tell us who the SIP Trunk SP was in this case, so others who may search for it here can also find the useful configuration you had them change.

Steve

m.junghage · ‎04-15-2010

Certainly, everything should be searchable :)

In this case the sip service provider was SIZE Mobile, they share the same technical platform as a couple other providers. So any provider using the Gotanet platform uses the same settings, configurations and so on as default.

(These providers are only available in Sweden)