Users Guide

624| Increasing Network Uptime Through Redundancy and VRRP Dell Networking W-Series ArubaOS 6.5.x| User Guide
9. (Optional) State synchronization improves failover performance by synchronizing client authentication
state information from the active controller to the standby controller. To use the state synchronization
feature, enter a pre-shared key into the Pre-shared key field. Note, however, that this feature is not
enabled until you complete the task in
step 13 on page 624
10.Click OK. The popup window closes, and the name of the new HA group appears in the HA Group
Configuration field on the Configuration > Advanced Services > Redundancy page.
11.(Optional)Select the Preemption checkbox to require APs that has failed over to a standby to attempt to
connect back to its original active controller once the controller is reachable again. When you enable this
setting, the AP will wait for the time specified by the lms-hold-down-period parameter in the ap system
profile before the AP attempts to switch back from the standby controller to the original controller.
12.(Optional) The standby controller over-subscription feature allows a standby controller to support
connections to standby APs beyond the controller's original rated AP capacity. To enable this feature, click
the Oversubscription checkbox.
13.(Optional) if you defined a pre-shared key in step 9 on page 624, select the State Synchronization
checkbox to enable this feature. (For more information about State Synchronization, see Client State
Synchronization on page 620)
14.(Optional) The inter-controller heartbeat feature allows for faster AP failover from an active controller to a
standby controller by enabling regular heartbeats between a standby controller and an active controller
15.Click Apply.
In the CLI
To configure a High Availability group using the command-line interface, access the CLI in config mode and
issue the following commands. The high availability group profile should be configured with a pair of IPv4
controller addresses and pair of IPv6 controller addresses to allow an IPv4 or IPv6 access point to establish a
connection to a standby controller.
ha group-profile <profile>
clone <profile-name>
controller <ipv4-ip-addr> role active|dual|standby
controller-v6 <ipv6-ip-addr> role active|dual|standby
heartbeat
heartbeat-interval <heartbeat-interval>
heartbeat-threshold <heartbeat-threshold>
no ...
over-subscription
pre-shared-key <key>
preemption
state-sync
A controller using the high availability features must be defined as a member of a high availability group. To
add a controller to the new high availability group, issue following CLI command:
(host)(config)#ha group-membership <ha-group>
Migrating from VRRP or Backup-LMS Redundancy
ArubaOS has a local management switch (LMS) and a backup LMS. In a typical deployment, the AP contacts the
master controller and is directed to the controller that handles the AP connection and traffic via the LMS
parameter. If the LMS becomes unreachable and a backup LMS is specified, the AP attempts to reconnect to
that backup controller. This function provides Layer 3 and site redundancy when this level of redundancy is
required.
High Availability: Fast Failover provides redundancy for APs, but not for controllers. Deployments that require master
controller redundancy should continue to use an existing VRRP redundancy solution.