HP StorageWorks Storage Mirroring Recover User's Guide (T5437-96008, November 2009)

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9. When the DNS configuration is complete, click OK to save your entries and return
to the Configure Protection window.
Note:
● If you are running Windows Server 2000 on the primary DNS server
hosting zones or domains that contain source and/or target resource
records, you must have the DNS WMI Provider installed on that DNS
server.
● The Dynamic updates setting for the DNS zone should be set to Secure
only. Otherwise, you must disable dynamic registration on the source
server in order to prevent the source from reclaiming its DNS record.
● If a hosts file entry for the source server exists on the client machine,
errors may occur during a failover and failback.
● Reverse lookup in DNS should be enabled. For more information about
enabling reverse lookup, refer to your Microsoft documentation.
● DNS registration for the private (devoted to Storage Mirroring Recover)
NIC IP should be disabled.
● If dynamic updates are enabled on a standard primary zone, the source
server will be able to update its DNS records after failover. To prevent this,
configure DNS to use an Active Directory-integrated zone.
● For more information about using the DNS Failover utility, access the
dfo.exe help by typing dfo.exe /? from a command prompt.
In order to set the primary DNS server with which the Application Manager will
communicate during failover, you must launch Application Manager using the command
line /blackberry /advanced option (dtam /blackberry /advanced). When launched in
the Advanced context, the Client DNS Server field will appear on the Configure DNS
Failover window. Use the Client DNS Server field to select the primary DNS server.
Identity failover
Select this option if you want to failover by transferring the source IP address and name
to the target. When using identity failover, it is possible that a name and/or IP address
conflict can occur either during failover or when the original source server comes back
online. To avoid this conflict, use DNS Failover.
Note:
Application Manager cannot be used for failover or failback when the Identity
failover method is selected. However, the Failover Control Center can still be
used to initiate failover. DNS failover reduces downtime and provides other
benefits. It is recommended for most environments.
In Identity Failover, the target’s physical identity is modified to match the source during a
failover. This includes the target adopting the source server’s name, primary IP address,