Cannot receive an external call

[Anastasiya2505]

Hello to everyone!

We've got such problem. We have an infrastructure consisting of VCS Control, VCS Expressway and MCU. VCS Expressway has dual NIC option enabled; LAN 1 has an internal IP address, LAN 2 - public IP (without NAT).

Both VCSs are configured according to manual (

http://www.cisco.com/en/US/docs/telepresence/infrastructure/vcs/config_guide/Cisco_VCS_Basic_Configuration_Control_with_Expressway_Deployment_Guide_X7-2.pdf), except NAT and Firewall settings - we don't have any.

When we call from our internal network (e.g. endpoint1@domain.com) to forein organization (endpoint2@foreindomain.com) - everything is ok. But we cannot receive any calls from outside.

An external DNS is also configured according to manual, domain name of VCE Expressway is externally resolvable.

Do you have any ideas what can be wrong? Thanks in forward.

[awinter2]

When outside callers are trying to call your organization, how are they trying to reach you, e.g what number/URI are they dialling?

If they are dialling 'alias@domain.com' where 'domain.com' is the domain your organization is using, have you made sure to create the appropriate H323 and SIP DNS SRV records in your public DNS server?

Do you see these inbound calls even hitting your VCS-E, e.g do you see these incoming call attempts in the search history or call history on your VCS-E?

[Anastasiya2505]

They are dialing 'alias@domain.com', all DNS records are created according to Cisco's recomendations.

In call history I don't see these calls, but in VCS-E's logs I can see that an external endpoint tries to call us.

[awinter2]

If you see the inbound call in the search history on the VCS-E, but not in the search history on the VCS-C, that implies that the call request never reaches your VCS-C which further indicates that you haven't set up the proper search rules on VCS-E towards VCS-C.

Do you have an AnyAlias search rule targetting the traversal zone towards VCS-C on the VCS-E?

[Anastasiya2505]

I don't see these calls in the search history on the VCS-E.

And yes, I have "Any Alias" mode in the search rule for the traversal zone on both VCSs.

[awinter2]

You previously stated that "In call history I don't see these calls, but in VCS-E's logs I can see that an external endpoint tries to call us.".

Later you state that "I don't see these calls in the search history on the VCS-E.".

Can you clarify where on the VCS-E you see that the external endpoint tries to call you, if it isn't in the search history you see this?

Could you tell us what domain you are using to route inbound calls, so that we can verify that SRV records are correct?

[Anastasiya2505]

In call/search history I don't see any records. But when I go to "Network logs" on VCS-E (with DEBUGGING level of logs) I see that forein endpoint tries to call us.

Domain -

[awinter2 · Accepted solution]

What exactly do you see in the network log? Can you paste it here? (Make sure to obfuscate sensitive information such as IP addresses and so forth).

It does not seem like you have created the required SRV records, such as

_h323ls._udp.

_h323cs._tcp.

_sip._tcp.

_sips._tcp.

at least I am not able to look up any of these SRV's from where I am.

- Andreas

[Anastasiya2505]

It seems to me there is really a mistake in SRV record. we'll solve it first.

I'm sorry for the trouble and thank you for help!

[Anastasiya2505]

can we now delete our domain from our posts?

[awinter2]

Yes feel free to remove the domain

- Andreas