Calls are failing between CUCM and Webex using LGW

[mohamedyare]

The outbound calls from CUCM to Webex Calling are failing, and an error SIP message is being received.

SIP/2.0 488 Not Acceptable Media
Via: SIP/2.0/TCP 192.168.1.20:5065;branch=z9hG4bKd1e23d546546
Warning: 399 192.168.1.100 "SRTP Offer/Answer not acceptable.RTP configured on dialpeer"

When dialing from the Webex client to a CUCM number, calls are not reaching the Local Gateway at all.

The Webex route pattern "4XXX" is pointed to a SIP Trunk, and the SIP Trunk shows as "Online.

LGW configuration andDebug output are attached for your consideration. Thanks in advance

[Bill]

Thanks Roger

I have attached the running config and debugs.
(I tweaked any **bleep**rds so they are not valid, but **bleep**es are intact)

It looks like dial-peer 100 is not matching incoming uri 100

I created a new incoming uri 101 with the IP of Webex, and if I use it, the calls work.

URI 100 is using the pattern 'dtg=SIP-MGCP0102115642_LGU' which is from the Webex LGW setup.
**bleep**e = SIP-MGCP0102115642_LGU

I am following this document for configuring the LGW.
https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling

According to the document, uri 100 has the pattern - dtg=SIP-MGCP0102115642_LGU
But in the SIP Invite, it is shown with lower case - dtg=sip-mgcp0102115642_lgu

I have tried both, and get the same results.

Thanks

[Bill]

**nny how the forum tweaked my tweaks.
It's supposed to mean that I tweaked the "p-words" but not the "u-names".
Hope these come through.

[Roger Kallberg]

Dial peer 100 should not use match on VIA header for Webex Calling. Remove this line and replace it with this.

no incoming uri via 100
incoming uri request 100

This is outlined in the document you referenced.

incoming uri request 100

To specify the voice class used to match a VoIP dial peer to the uniform resource identifier (URI) of an incoming call.

[Bill]

Thank you for catching that Roger.
That is how it was originally, but when I changed to URI 101, I changed it to 'uri via', but never set it back.
I just set it back to 'uri request' and it fails.
But that is when the **bleep**e is using Caps.
I set the **bleep**e to lowercase and now it works.
Thanks for the feedback. That fixed it.
I guess I need to be careful. Following the document, they show to configure uri 100 with the **bleep**e that Webex gives us.
But it needs to be set to lowercase even though Webex gives it in Uppercase (at least in my case).

[Bill]

I would mark this as Correct Answer, but I don't see the button to do that.

[Roger Kallberg]

Only the OP can do that and since you asked your question in someone else post you cannot do that.

[Bill]

Of course I cannot upload the debugs.

[Bill]

Here are the debugs in a Word document.
Hope this is usable, 
The forum will not let me upload the debug file as a txt file.
It said the content didn't match the file extension.