Instruction manual

Chapter 3: High Availability
NetScaler 9000 Series Installation and Configuration Guide - Volume 1 3-15
NSICG60_JAN05
synchronization between the nodes in an HA pair, you need to execute the
Force Sync command.
You can execute this command both on the primary and secondary nodes.
However, if synchronization is already in progress, the command will not
work and the NetScaler system will display a warning.
This command will not work when:
z Executed on a standalone NetScaler system
z HA is disabled on the NetScaler system
z HA synchronization is disabled on the NetScaler system
The “Done” message displayed after you execute the force sync command
does not indicate that the synchronization has been successful. To verify
whether the operation has been successful, execute the
show node
command. This command indicates whether the nodes are synchronized.
3.7 Force Failover of the Primary NetScaler 9000
System
Force fail over is used to forcibly make the Secondary device take over as the
Primary device. For example, lets have an existing HA setup where Machine
A is the Primary device and Machine B is Secondary device. If there is a
requirement to upgrade Machine A with a hardware component, then
Machine B should take over and function as the primary device until Machine
A is upgraded. To accomplish this the
force ns fail over CLI command
is used. This command can be executed from the Primary or the Secondary
device.
Note: If the force ns failover CLI command is executed on a
Standalone, it returns the error message “Operation not permitted on
Standalone node.”
The
force ns failover CLI command will not be propagated or
synchronized. There is no dependency between the
force ns failover
CLI
command and synchronization. Synchronization will happen
automatically whenever there is a change in the Primary. To see the status of
synchronization after Force Failover, execute the
show ns node CLI
command to see if there are any errors in the synchronization process.