Failover ip address placeholders, Failover ip address placeholders -20, Updating the number of ip address placeholders – HP Storage Mirroring Software User Manual
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Failover IP address placeholders
For Windows NT 4.0, IP address placeholders exist so that during the failover process, the source’s IP address can be assumed
by the target without requiring a target machine reboot. The number of placeholders defined must be the maximum number
of IP addresses for which the target adapter will need to respond. If all of the defined placeholders have been replaced due to
failovers, the target cannot assume or respond for any additional IP addresses.
For example, suppose the following:
10 placeholders defined
3 machines being monitored
2 network adapters on each machine
2 IP addresses assigned to each adapter
Therefore:
2 IP addresses X 2 network adapters X 3 machines = 12 total IP addresses
If Storage Mirroring is set to monitor each IP address, on each adapter, on each machine, and all three machines failed, there
are not enough placeholders available for the target to respond for every address. The last two IP addresses to fail do not get
assumed by the target. Placeholders may have been created during the Storage Mirroring installation depending on the options
you chose. The maximum number of placeholders allowed is 99.
Updating the number of IP address placeholders
1.
From the Failover Control Center window, select
Settings
,
Placeholders
.
2.
Modify the setting if necessary. Click
Set
to save the new configuration and reboot the machine, or
Close
to exit
without saving the new setting.
NOTE:
When the
Set
button is selected, a message box prompts to reboot the machine. A reboot is necessary
to reinitialize the target adapter.
!
Select
Yes
to set the new placeholder value and reboot the machine.
!
Select
No
to set the new placeholder value, but a manual reboot will still be required to use this
machine as a failover target.
!
Select
Cancel
to not reboot the machine. The new placeholder value will not be set.
The number of placeholders is set independently for each NIC on a Windows NT 4.0 machine. For
example, if you change the number of placeholders to 7 for one NIC, all other NICs on that machine will
automatically be changed to 7 placeholders.