HP OpenView Storage Mirroring High Availability for Exchange Server 2000/2003 Application Notes (May 2005, T2558-88020)

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1. On the Monitor Settings window, only select Server Name under Items to Failover. Do not select
IP Address(es) to failover. This corresponds to step 9 in ”Configuring failure monitoring” on
page 9.
2. After failover and failback, you will need to update DNS. This can be done manually after the
failover/failback is complete, or can be done during the failover process as part of the failover
script postover.bat (step 1 in ”Configuring failure monitoring” on page 9) and failback script
preback.bat (step 3 in ”Configuring failure monitoring” on page 9). Three possible options for
updating DNS are outlined below.
a. Manual DNS updates—You can update the DNS server manually by using the Windows
Administrative Tools (Start, Programs, Administrative Tools, DNS).
b. Automated/Scripted updates using DNSCMD—The DNS Server Troubleshooting Tool utility
(DNSCMD), which can be found in the Windows 200x support tools, can be used in the
Storage Mirroring failover and failback scripts to delete and add host and reverse lookup
entries so that the source host name will resolve to the target IP address. The types of DNS
records that will need to be modified vary by implementation but may include A, MX, and
CNAME records.
For example, the following commands would be added to the end of the failover script
(postover.bat). The second and fourth lines are identical to what appears on the PTR
record's properties in the Windows 200x DNS utility.
dnscmd dns_server_name /RecordDelete domain_name source_name A
source_IP_address /f
dnscmd dns_server_name /RecordDelete reverse_subnet_IP.in-addr.arpa
reverse_lookup_IP PTR source_server_name /f
dnscmd dns_server_name /RecordAdd domain_name source_server_name A
target_IP_address
dnscmd dns_server_name /RecordAdd reverse_subnet_IP.in-addr.arpa
reverse_lookup_IP PTR source_server_name
dnscmd dns_server_name /RecordDelete domain_name @ MX 10
Source_Name.domain_name /f
dnscmd dns_server_name /RecordAdd domain_name @ MX 10
Target_Name.domain_name
For example, the following commands would be added to the end of the failback script
(preback.bat). The second and fourth lines are identical to what appears on the PTR
record's properties in the Windows 200x DNS utility.
dnscmd dns_server_name /RecordDelete domain_name source_name A
target_IP_address /f
dnscmd dns_server_name /RecordDelete reverse_subnet_IP.in-addr.arpa
reverse_lookup_IP PTR source_server_name /f
dnscmd dns_server_name /RecordAdd domain_name source_server_name A
source_IP_address
dnscmd dns_server_name /RecordAdd reverse_subnet_IP.in-addr.arpa
reverse_lookup_IP PTR source_server_name
dnscmd dns_server_name /RecordDelete domain_name @ MX 10
target_name.domain_name /f
dnscmd dns_server_name /RecordAdd domain_name @ MX 10
source_name.domain_name
DNSCMD commands will only work if dynamic updates are enabled on the DNS zone. This
is configured on the DNS zone Properties dialog box in the Windows Microsoft
Management Console DNS snap-in. If Only Secure Updates is enabled (this option is
available only on Active Directory integrated zones), the DNSCMD utility must be used in
the context of a user who is in the domain DnsAdmins group. This means the Storage
Mirroring service logon account must be in the DnsAdmins group if the commands are in
failover and failback scripts. The Account option in the Storage Mirroring Monitor Settings
does not apply to the failover and failback scripts, so verify the Storage Mirroring service
logon account is in the DnsAdmins group.