Create a DNS SRV Record for Integration with Hosted Exchange UM


Topic Last Modified: 2012-10-18

This topic describes how to configure the Domain Name System (DNS) SRV record that is required for a Lync Server 2010 Edge Server to route to a hosted Exchange service such as Microsoft Exchange Online.

  1. Log on to the external DNS server as a member of the DnsAdmins group.

  2. Click Start, click Administrative Tools, and then click DNS.

  3. In the console tree for your SIP domain, expand Forward Lookup Zones, and select the SIP domain in which Lync Server 2010 will be installed.

    You must create the DNS SRV record in the SIP domain in which Lync Server is or will be installed. When you create the SRV record, the FQDN used for the Host offering this service field must be the external FQDN of the Edge pool. For example, if the external FQDN of your Edge pool is, enter that value. This must also be in the same domain as the DNS Hosts (A) record.
  4. Right-click the selected domain, and then click Other New Records.

  5. In Resource Record Type, click Service Location (SRV), and then click Create Record.

  6. In New Resource Record, click Service, and then type _sipfederationtls.

  7. Click Protocol, and then type _tcp.

  8. Click Port Number, and then type 5061.

  9. Click Host offering this service, and then type the fully qualified domain name (FQDN) of the Lync Server Edge Server pool that provides access to your Lync Server system for trusted external clients.

    The domain must also be set up as an authoritative, accepted domain in your Exchange Online settings. For details, see Create Accepted Domains at
  10. Click OK, and then click Done.

  1. Log on to a client computer in the domain.

  2. Click Start, and then click Run.

  3. At the command prompt, run the following command:

    nslookup <FQDN Lync Edge Pool>
  4. Verify that you receive a reply that resolves to the appropriate IP address for the FQDN.