No Audio on calls to external numbers that are setup on the same system (different offices)

[tomtom9]

Hi all,

We have recently change our top level firewalls to Meraki. In order to get the IPO system working fine for calls we had to apply external IP in Network topology and set SIP trunks to use equivalent Network Topology so the calls were able to go through and are not rejected by the SIP Trunk provider. Previous setup did not require this - we had SIP ALG and SIP Helper disabled on previous firewall, Meraki does not support ALG at all.

Issue identified today is that when calling calling from one office to another via external number (both setup on the same IPO) no audio can be heard. I assume this is because the call comes out on the same public IP to the SIP Trunk provider and then comes back - to the same originating IP. The connection is established but no audio can be heard on any of the sides. Maybe some UDP ports are not opened?

Any ideas would be greatly appreciated.

Regards,
T

 

[amriddle01]

Why even do that? Makes no sense, just call extension direct

But the issue is clearly the firewall, we arent best placed to help with that

 

[intrigrant]

https://documentation.meraki.com/zG...Cisco_Meraki:_F.A.Q._and_Troubleshooting_Tips

 

[tomtom9]

Thanks guys.

Call extension direct - yeah, if it was that easy

Re documentation, that is helpful and we have already been through it. As a test I have unblocked all ports on the Meraki and it is still failing on the audio side for the calls mentioned.

One thing I noticed in the logs when such call happens is:

Info: media ports will be changed due to NAT traversal.

Anything that can be adjusted on the Avaya end to prevent this?

Cheers.

 

[IPGuru]

Call extension direct - yeah, if it was that easy

What's Difficult about it?
instead of dialling the DDI you dial the extn's, extn number!
or do your prefer to pay unnecessary call charges?

it is even possible to create a shortcode such that if someone is stupid enough to dial the full DDI it gets translated to an internal call


Do things on the cheap & it will cost you dear

 

[teletechman]

are you not set up as an SCN?
Mike

 

[tomtom9]

Dont ask me what is difficult about it Users will still use external number. We are on Free national calls so it does not matter really re cost.

We have setup shortcodes for those numbers to revert to Internal Extension (Groups). So this workaround is fine for now.

Sorry Mike, SCN?

Thanks to all who contributed.

 

[teletechman]

Small Community networking. Do you have an IP Office at each office or just IP Phone or are you running different brands of phone systems at each office.
Mike

 

[IPGuru]

teletechman
as he original post says each user is on the same system & uses the same internet connection I would take it that when the OP says different offices he means different rooms in the same building & not users on different systems in different premises.


Do things on the cheap & it will cost you dear

 

[teletechman]

@IP Guru OK I see what you are saying

 

[tomtom9]

It is actually users on the same system in different locations (geographically) using different external numbers but on the same Private Network - with same breakout point to the Internet. It does not matter though whether they are in the same building or not. They share same external IP.

 

[IPGuru]

close enough, it is still a data routing issue - direct media path is possibly getting confused?

It is still a daft idea to dial the external number when an internal number will suffice & provide better service (indication of phone status, correct display of who is calling etc)



Do things on the cheap & it will cost you dear