To integrate on-premises Lync Server 2010 with Exchange Online, you must configure a shared SIP address space (also called a split domain). We need to follow below steps in the on-premise Lync environment. Actually, these steps are also mandatory for configuring Hosted Voicemail
- Check SRV records
- Check setting "Enable partner domain discovery" in Access Edge configuration
- Configure Lync Edge server for Integration with Hosted UM
First, you have to check the presence of the Lync DNS SRV records.
These records are required for a Lync Edge server to route to a hosted Exchange such as Office 365.
To verify the presence of the SRV record, follow these steps :
- Log on to a client computer in the domain.
- Click Start, and then click Run.
- At the command prompt, run the following command:
- Nslookup _sipfederationtls._tcp.domain.com
This should return the name of the DC, its IP address and the record name.
If it returns a non-existent domain, follow this Technet Article.
Please note that the SRV records need to be in your external domain name DNS zone when using split DNS.
The next step is to check if the setting "Enable partner domain discovery' is enabled in the access edge configuration.
Steps to check this can be found in the following article :
The next step is configuring the Lync Edge server for Integration with Office 365 OWA
If you already configured Federation on you edge server, you can skip the "Set-CsAccessEdgeConfiguation" cmdlet. ( verify below settings using the Get-CsAccessEdgeConfig | fl)
If you haven't set up federation yet, log on to your Lync server and open up an elevated Lync Server Management Shell.
Use the "Set-CsAccessEdgeConfiguration -AllowFederatedUsers $True" to allow Federation.
Use the "Get-CsAccessEdgeConfiguration | fl" to verify this changed the "AllowFederatedUsers" to true.
The last thing we have to set up is a HostingProvider for Office 365.
Use the same Lync Server Management Shell to do this.
Use the below cmdlet to add the Office 365 Hosting Provider.
"New-CsHostingProvider -Identity “Hosted UM” -Enabled $True -EnabledSharedAddressSpace $True –HostsOCSUsers $False -ProxyFqdn "exap.um.outlook.com" –IsLocal $False -VerificationLevel UseSourceVerification"
Use the "Get-CsHostingProvider" to verify that the hosting provider has been made.
Source : Technet Article
Now, the only thing we have to do is wait for replication between the Lync server and the Lync Edge.
After some time, you should see that IM is working within Office 365 OWA.