Skype For Business On-premise Hybrid with existing sub-domain in O365

[larsstavnas]

Hello,

We have a sip-domain "contoso.com" on-premise and our students have "students.contoso.com" sip-domain located in SfB Online only.

Just tried to setup Skype For Business On-premise 2015 to a hybrid with Office365. Everything worked except federation/presence status from cloud domain (students.contoso.com) to on-premise domain.

After I ran a debug I encountered this error:

"ms-diagnostics: 1017; reason="Cannot route From and To domains in this combination"; summary="Domain type analysis indicates that the ms-split-domain-info header in the message is the wrong type”"

Which pointed me to the MS article here:

https://docs.microsoft.com/en-us/skypeforbusiness/troubleshoot/hybrid-im-presence/sfb-online-users-c...

So my question to you guys, to get this working from what I understand I need to take "students.contoso.com" in public facing certificates on my on-premise edge and I also need to point federation DNS records to this domain on-premise. But what about other DNS records? Should this domain be a part of my topology? How much work do I need to do internal with simple urls, dns, certificates and so on. All our users in this domain will still contain Online.

I struggled to find this scenario exactly online.

Any answers would be much appreciated.

[#2]

@larsstavnas did you find a solution to this problem?

[#3 · Accepted solution]

@einmberg 

Hello Myhren, thank you for showing interest in this post.

I actually answered the solution in my own question, I just had to add the subdomain to the external facing certificate and then our edge servers would to the rest of the magic.

If you have any further questions, don't hesitate.