Avaya CM 5.2.1 co-resident SES 5.2.1 SIP Trunk not working

[flore425]

Hi everyone,

I really need your expertise with this!

I am implementing a SIP Trunk from Avaya CM to a third-party SIP Provider through a co-resident SES, but it seems that it is not working. I have already referred to different Application Notes but it is still not working. I have also configured SES according to what the Application Notes stated. Licenses for SES are still working, certificates are far from expiry, conflict trunks we're removed.

I always get a Network Failure for my outbound call and incoming call are not passing through (with no trace capture on ASA), SES Trace logger has no trace capture of my test calls.
I configured my SIP Domain to be the same as the address of the procr.

Do we really need to configure a DNS for the Avaya CM? or is it okay if it is left blank?

Also, can we implement direct SIP Trunking from CM to SIP Provider without the co-resident SES?

These are some of the application notes I have referred to:

https://www.devconnectprogram.com/fi...6-fe7b6188230c

https://downloads.avaya.com/css/P8/documents/100114858

Really hope someone can help me with this.

Thank you everyone.