13.4 Migrating DNS to Another Domain Controller

In a typical DSfW deployment, beginning OES2 SP3, any domain controller can be configured as a DNS server. If the domain controller serving as primary DNS server does not function due to a hardware or software fault, the other domain controllers need at least one DNS server to keep the domain services intact.

IMPORTANT:The DNS migration can happen even when the source DNS server is down. If the DNS server is down, make sure that any of the subsequent domain controllers in the forest have the replica of the Tree Root partition. This is necessary to perform Step 2.

When the first domain controller goes down, make sure that the configuration partition and schema partition replica is there on at least one domain controller in the domain. This is required to keep the functioning of DSfW intact.

To migrate the DNS server from the first domain controller, from the subsequent domain controller execute the following steps:

  1. Using the CASAcli client utility, set the CASA credentials on the subsequent domain controller with the following commands.

    KEYVALUE=<dns-admin_dn> CASAcli -s -n dns-ldap -k CN

    KEYVALUE=<password> CASAcli -s -n dns-ldap -k Password

  2. Using iManager, execute the following steps:

    1. Click DNS>DNS Server Management>Create Server option.

      Specify the NCP server name of the subsequent domain controller, hostname and the domain name for the server object.

    2. Click DNS>DNS Server Management>View/Modify Zone option.

      1. Select the DNS zone from the list. Click OK.

      2. Associate the zone with the DNS server. For details on associating zone with a DNS server, see Zone Management in the OES 2 SP3: Novell DNS/DHCP Administration Guide

  3. Restart novell-named on the subsequent domain controller using the following command:

    rcnovell-named restart

After migrating the DNS server to the destination domain controller, the DNS entry referencing the first domain controller is still retained in the cache for some time. This does not affect the functionality in any way as when a name resolution request is issued, it gets resolved by the DNS server on the other domain controller, if the first domain controller has not responded.

IMPORTANT:If you have changed any DNS records or the configuration file, the changes are effected after the dynamic reconfiguration interval of DNS. The default value of this interval is 15 minutes. If the changes are not done, we recommend you to restart the DNS server using the rcnovell-named restart command.