WESM zl Management and Configuration Guide WT.01.28 and greater

10-10
Redundancy Groups
Configuring a Redundancy Group
Note At most four managers can access a group’s redundancy group configuration mode
context at once.
For more information on CLI commands, see Appendix A: “ProCurve Wireless Edge
Services zl Module Command Line Reference.”
Redundancy Group Behavior When a Member Fails
Members of a redundancy group listen for heartbeats from every other member. If,
over the duration of the hold period, modules miss heartbeats from one member,
standby members load balance the failed member’s RPs among themselves. If you
desire, you can configure adoption preference IDs to control which of several standby
modules adopt particular RPs.
Active members take no action when another member of the group fails unless, for
whatever reason, the standby members fail to adopt the orphaned RPs. For example,
a failed network connection might isolate a standby member from the RPs, or manual
adoption might be inadvertently enabled on the standby member. If a redundancy
group consists of only active members, active members can also adopt a failed
members’ RPs, load balancing the RPs among themselves.
When the active member becomes functional again, the standby modules continue
to support the RPs. You can manually force the standby modules to revert the RPs to
the recovered member. You cannot, however, force an active member to return any
RPs that it may have adopted. (See “Reverting RPs Adopted by a Standby Member
to the Active Member” on page 10-32.)
Configuring a Redundancy Group
When you configure a redundancy group, you must define the following on each
module that is a member of the group:
■ the interface IP address for the module that you are configuring
■ the member IP addresses (which are the IP addresses for the other modules in
the redundancy group)
These two settings enable each module to send messages to and receive messages
from other modules. The interface IP address that you enter on the one module should
be the member IP address that you enter on each of the other modules. Table 10-2
provides an example.