Hello,
In a scenario with a CMS acting only as SFB gateway:
endpoints <->VCS C<->CMS<->FE<->MS Edge<->Internet (O365)
This customer is experiencing problems to launch outgoing calls (calls from VC to external SFB clients don´t complete).
The incoming call works fine (from customer SFB on O365 cloud to an endpoint registered t the VCS Control).
Calls to internal SFB works fine on both direction.
Endpoints use: @vc.domain.com
SFB on O365 use: @domain.com
To be able to make calls using the MS Edge, the CMS register and use an account created specific for this, where it asks for the Edge information using MRAS and receive this information from via FE.
Troubleshooting the comunication, we can observe this behaviour, the CMS generates e SDP with the received information and then the SFB rejects the call with:
SIP/2.0 504 Server time-out
ms-diagnostics: 1041;reason="Peer server pool is out of service";pool-size="2";pool="sip.vc.domain.com";port="5061";source="sip.domain.com"
Does anyone saw this message and have a clue what they need to configure at the SFB side to allow this?
I did a quick test using the parameter to do not passthrough the CallerID (use dial plan), where the outbound rule use the server name (cms.server.localdomain.com) to establish the SIP trunk with the FE and the error changes:
ms-diagnostics: 1008;reason="Unable to resolve DNS SRV record";domain="cms.server.localdomain.com";dns-srv-result="NegativeResult";dns-source="InternalCache";source="sip.domain.com"
And looks OK, because the internal name is not resolvable at MS Edge.
Any ideas?
Maybe they need to configure the VC domain somewhere inside the SFB configuration?
The external SRV Records for this domain already exists and point to the Edge, but the Edge don´t have this domain (vc.domain.com) configured in the topology nor in its certificate.
Thanks
