DNS Records for Front End Pools

Front End pool with multiple Front End Servers and a hardware load balancer (whether or not DNS load balancing is also deployed on that pool)

An internal A record that resolves the fully qualified domain name (FQDN) of the Front End pool to the virtual IP (VIP) address of the load balancer.

Front End pool with DNS load balancing deployed

A set of internal A records that resolve the FQDN of the pool to the IP address of each server in the pool. There must one A record for each server in the pool.

Front End pool with DNS load balancing deployed

A set of internal A records that resolve the FQDN of each server in the pool to the IP address of that server. For details, see DNS Load Balancing in the Planning documentation.

Front End pool with a single Front End Server and a dedicated back-end database but no load balancer

An internal A record that resolves the FQDN of the Front End pool to the IP address of the single Enterprise Edition Front End Server.

Automatic client sign-in

For each supported SIP domain, an SRV record for _sipinternaltls._tcp.<domain> over port 5061 that maps to the FQDN of the Front End pool that authenticates and redirects client requests for sign-in. For details, see DNS Requirements for Automatic Client Sign-In.

Device Update Web service discovery by unified communications (UC) devices

An internal A record with the name ucupdates-r2.<SIP domain> that resolves to the IP address of the Front End pool that hosts the Device Update Web service. In the situation where a UC device is turned on, but a user has never logged into the device, the A record allows the device to discover the Front End pool hosting Device Update Web service and obtain updates. Otherwise, devices obtain this information though in-band provisioning the first time a user logs in. For details, see Updating Devices in the Planning documentation.

Important:
If you have an existing deployment of Device Update Web service in Lync Server 2010, you have already created an internal A record with the name ucupdates.<SIP domain>. For Microsoft Office Communications Server 2007 R2, you must create an additional DNS A record with the name ucupdates-r2.<SIP domain>.

A reverse proxy to support HTTP traffic

An external A record that resolves the external web farm FQDN to the external IP address of the reverse proxy. Clients and UC devices use this record to connect to the reverse proxy. For details, see Determining DNS Requirements in the Planning documentation.

webcon.contoso.com

ee-pool.contoso.com

DNS A record for the ee-pool.contoso.com that resolves to the VIP address of the load balancer used by the Front End Servers.

DNS A record for webcon.contoso.com that resolves to the VIP address of the load balancer used by the Front End Servers.

ee-pool.contoso.com

ee-pool.contoso.com

DNS A record for ee-pool.contoso.com that resolves to the virtual IP (VIP) address of the load balancer used by the Enterprise Edition Front End Servers in the Front End pool.

Note that if you are using DNS load balancing on this pool, your Front End pool and internal web farm cannot have the same FQDN.