Forum Discussion

Anonymous's avatar
Anonymous
Oct 21, 2017
Solved

Hybird SIP domain

If we plan to hybrid a sip domain on the tenant,  but they have five sip domains. I know if we plan to hybrid one sip domain and we need to hybrid four domains on a same tenant. For the DNS, can we...
Federation
Installation
  • Damien Margaritis's avatar
    Damien Margaritis
    Oct 22, 2017

    Hi John,

     

    I wrote a detailed response that keeps being posted as an answer then mysteriously disappearing... Let me try just posting the summary, then the full post:

     

    Summary

     

    • SIP Domains only on Skype for Business Online: point all records to cloud
    • SIP Domains on-prem and online (hybrid), point to on-premises Edge server(s) & Reverse Proxy
      • Edge server certificate will always require an additional SAN entry
      • Reverse Proxy certificate won't if you are happy to allow lyncdiscover over http (port 80)

     

Damien Margaritis's avatar
Damien Margaritis
Iron Contributor
Oct 22, 2017

Hi John,

 

I wrote a detailed response that keeps being posted as an answer then mysteriously disappearing... Let me try just posting the summary, then the full post:

 

Summary

 

  • SIP Domains only on Skype for Business Online: point all records to cloud
  • SIP Domains on-prem and online (hybrid), point to on-premises Edge server(s) & Reverse Proxy
    • Edge server certificate will always require an additional SAN entry
    • Reverse Proxy certificate won't if you are happy to allow lyncdiscover over http (port 80)

 

Damien Margaritis's avatar
Damien Margaritis
Iron Contributor
Oct 22, 2017

For any SIP domains that only exist in Office 365, all DNS records can point to Office 365. There are 4 records per domain that you need to configure:

 

SRV Records

 

TypeServiceProtocolPortWeightPriorityTTLNameTarget

SRV_sip_tls44311001 hour<DomainName>sipdir.online.lync.com
SRV_sipfederationtls_tcp506111001 hour<DomainName>sipfed.online.lync.com

 

CNAME Records

 

TypeHost nameDestinationTTL

CNAMEsip.<DomainName>sipdir.online.lync.com1 hour
CNAMElyncdiscover.<DomainName>webdir.online.lync.com1 hour

 

For any hybrid SIP Domains, domains that exist in both Skype for Business On-Premises and Skype for Business Online, all DNS records need to point to your on-premises Edge Server(s) and Reverse Proxy.

 

This does of course impact the number of SANs required on your public certificates. However, if you follow the below guidance you can limit the number of SANs required on your Reverse Proxy certificate

Resources