"You are operating in a split-domain (hybrid) topology" warning when you configure an Office 365 call queue in Skype for Business admin center

Symptoms

After you set an Office 365 call queue in the Skype for Business admin center, and you add a distribution group, agents or users are not called. Additionally, when you change the call queue, you may receive the following warning message:

Warning: you are operating in a split-domain (hybrid) topology.

Currently, this application is only supported for pure online tenants.

You may proceed with configuration at your own risk.

Cause

This issue occurs because your tenant is configured by using a split domain that is currently not supported for Organizational Auto Attendant (OrgAA) or call queues.

However, if you follow the guidance in the "Workaround" section, your call queue may work if all users who are defined as agents are working in Office 365 and are appropriately licensed.

Workaround

To work around this issue, follow these steps:

  1. Make sure that the on-premises deployment for Skype for Business and Office 365 is configured correctly for hybrid voice.

  2. Enable your Edge server to accept calls that are routed from sipfed.resources.lync.com (part of a typical hybrid configuration).

  3. Configure a new hosting provider in your on-premises configuration that enables communication to the Azure services that function as part of the OrgAA and call queue infrastructure. To do this, run the following cmdlet in Remote PowerShell:

    New-CSHostingProvider -Identity SFBOnlineResources -ProxyFqdn "sipfed.resources.lync.com" -Enabled $true -EnabledSharedAddressSpace $true -HostsOCSUsers $true -VerificationLevel AlwayVerifiable -IsLocal $false
    
  4. Make sure that domain that's specified for the call queue is the sip domain of the agents. Also, make sure that all agents in the queue are in the same sip domain. Do not specify "contoso.mail.onmicrosoft.com" or "onmicrosoft.com." If the domain was selected incorrectly when you created the call queue, you must re-create the call queue or OrgAA by using the correct domain.

More Information

To verify which agents are available to receive calls among the agents who are defined in the distribution list for a call queue, run the following cmdlet in Remote PowerShell:

Get-CsHuntGroup

If the agents are not listed,follow these steps:

  1. Verify that the agents are licensed for Skype for Business and Cloud PBX.

  2. Verify that the agents are Enterprise Voice-enabled. If they are assigned a PSTN Calling license, they will be Enterprise Voice-enabled already. If they have only a Cloud PBX license, you must manually enable them for Enterprise Voice. To determine whether it's necessary to enable the user for Enterprise Voice, run the following script from Remote PowerShell:

    Get-CsOnlineUser -Identity <UPN or SIP Address> | Select SipAddress, EnterpriseVoiceEnable, HostedVoiceMail
    Set-CsUser -Identity <UPN or SIP Address> -EnterpriseVoiceEnable $True -HostedVoiceMail $True
    

For more information, see the following TechNet topics: