How-To: Set Correct Nameserver and Forwarder Entries for UCS Servers



How to set correct nameserver and forwarder entries for UCS servers

UCS (and ActiveDirectory) relies on reliable DNS resolving. It is very important to have DNS up and running correctly.

Step 1: Set forwarder

The forwarder will resolve all non-local domains so you will be able to access Internet services. You have to decide if you use the DNS server of your Internet provider or if you use some public available servers.
Ideally, you should set at least a second forwarder as fallback in case of failure. If you have a choice, use the DNS servers close to your geographical location.

ucr set dns/forwarder1= \
        dns/forwarder2= \

Step 2: Set nameserver for your local network

On each UCS server (except member server) you should set it’s own IP as first nameserver and then add the IP addresses of other UCS hosts in order to get some load balancing and fallback in case of failure. You should NOT use the localhost address ( here:

ucr set nameserver1=<IP of this UCS server> \
        nameserver2=<IP of other UCS server> \
        nameserver3=<IP of third UCS server>

For UCS systems with the role “Member server” use the IP addresses of a UCS Master, Backup and/or Slave of your domain.

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