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ha

ha group-membership <group-membership>

ha group-profile <profile-name>

clone <source>

controller <ip> role {active|dual|standby}

controller-v6 <ipv6> role {active|dual|standby}

heartbeat

heartbeat-interval <heartbeat-interval>

heartbeat-threshold <heartbeat-threshold>

no

over-subscription

pre-shared-key <pre-shared-key>

preemption

state-sync

Description

This command configures the High Availability:Fast Failover feature by assigning a managed device or standby controller to a high-availability group, and defining the deployment role for each controller.

Parameter

Description

Range

Default

group-membership

<group-membership>

Displays the high availability group in which the managed device or standby controller is a member.

ha group-profile

<profile-name>

Creates a new high availability group, or define settings for an existing group.

clone <source>

Name of an existing high availability profile from which parameter values are copied.

controller <ip>

IPv4 address of a controller that should be added to the specified high availability group.

    role

Assign one of the following roles to each controller in the high availability group.

Active: Controller is active and is serving APs.

Dual: Controller serves some APs and acts as a standby controller for other APs.

Standby: Controller does not serve APs, as only acts as a standby in case of failover.

controller-v6 <ipv6>

IPv6 address of a controller that should be added to the specified high availability group.

    role

Assign one of the following roles to each controller in the high availability group.

Active: Controller is active and is serving APs.

Dual: Controller serves some APs and acts as a standby controller for other APs.

Standby: Controller does not serve APs, as only acts as a standby in case of failover.

heartbeat

The high availability inter-controller heartbeat feature allows for faster AP failover from an active controller to a standby controller, especially in situations where the active controller reboots or loses connectivity to the network.

NOTE: For more information about this feature, see High Availability Inter-Controller Heartbeats

heartbeat-interval <heartbeat-interval>

Enter a heartbeat interval in the Heartbeat Interval field to define how often inter-controller heartbeats are sent.

100-1000 ms

100 ms

heartbeat-threshold <heartbeat-threshold>

Enter a heartbeat threshold in the Heartbeat Threshold field to define the number of heartbeats that must be missed before the APs are forced to fail over to the standby controller.

3-10 heartbeats

5 heartbeats

no

Negates or removes any configured parameter.

over-subscription

The standby controller over-subscriptionA business model where a customer pays a certain amount as subscription price to obtain access to a product or service. feature allows a standby controller to support connections to standby APs beyond the controller's original rated AP capacity.

A  controller acting as a standby controller can oversubscribe to standby APs by up to four times that controller's rated AP capacity, as long as the tunnels consumed the standby APs do not exceed the maximum tunnel capacity for that standby controller.

NOTE: For more information about this feature, see High Availability with Extended Capacity

pre-shared-key

<pre-shared-key>

Define a PSKPre-shared key. A unique shared secret that was previously shared between two parties by using a secure channel. This is used with WPA security, which requires the owner of a network to provide a passphrase to users for network access. to be used with the state synchronization feature.

NOTE: For more information about this feature, see Client State Synchronization

8-32 characters

preemption

If you include this optional parameter to enable preemption, an AP that has failed over to a standby controller attempts to connect back to its original active controller once that 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 profile before the standby AP attempts to switch back to original controller.

state-sync

State synchronization improves failover performance by synchronizing PMKPairwise Master Key. PMK is a shared secret key that is generated after PSK or 802.1X authentication. and Key cache values from the active controller to the standby controller, allowing clients to authenticate on the standby controller without repeating the complete 802.1X802.1X is an IEEE standard for port-based network access control designed to enhance 802.11 WLAN security. 802.1X provides an authentication framework that allows a user to be authenticated by a central authority. authentication process.

NOTE: To use the state synchronization feature, configure a PSKPre-shared key. A unique shared secret that was previously shared between two parties by using a secure channel. This is used with WPA security, which requires the owner of a network to provide a passphrase to users for network access. with the pre-shared-key parameter. For more information about this feature, see Client State Synchronization

Usage Guidelines

The High Availability:Fast Failover feature supports redundancy models with an active controller pair, or an active or standby deployment model with one backup controller supporting one or more active controllers. Each of these clusters of active and backup controllers comprises a high-availability group. Note that all active and backup controllers within a single high-availability group must be deployed in a single master-local topology. The High Availability:Fast Failover features works across Layer-3 networks, so there is no need for a direct Layer-2 connection between controllers in a high-availability group.

By default, the active controller of an AP is the controller to which the AP first connects when it comes up. Other dual mode or standby mode controllers in the same High Availability group become potential standby controllers for that AP. This feature does not require that the active controller act as the configuration master for the local standby controller. A master controller in a master-local deployment can act as an active or a standby controller.

When the AP first connects to its active controller, that controller sends the AP the IP address of a standby controller, and the AP attempts to connect to the standby controller. If an AP that is part of a cluster with multiple backup controllers fails to connect to the first standby controller, the active controller will select a new standby controller for that AP, and the AP will attempt to connect to that standby controller. APs using control plane security establish an IPsecInternet Protocol security. IPsec is a protocol suite for secure IP communications that authenticates and encrypts each IP packet in a communication session. tunnel to their standby controller. APs that are not configured to use control plane security send clear, unencrypted information to the standby controller.

An AP will failover to its backup controller if it fails to contact its active controller through regular heartbeats and keepaliveSignal sent at periodic intervals from one device to another to verify that the link between the two devices is working. If no reply is received, data will be sent by a different path until the link is restored. A keepalive can also be used to indicate that the connection should be preserved so that the receiving device does not consider it timed out and drop it. messages, or if the user manually triggers a failover using the WebUI or CLICommand-Line Interface. A console interface with a command line shell that allows users to execute text input as commands and convert these commands to appropriate functions..

A controller using this feature can have one of three high-availability roles: active, standby, or dual. An active controller serves APs, but cannot act as a failover standby controller for any AP except the ones that it serves as active. A standby controller acts as a failover backup controller, but cannot be configured as the primary controller for any AP. A dual controller can support both roles, and acts as the active controller for one set of APs, and also acts as a standby controller for another set of APs.

Examples

The following commands configure a high availability group:

(host) [mynode] (config) #ha group-profile new

(host) [mynode] (HA group information "new") #controller 192.0.2.2 role active

(host) [mynode] (HA group information "new") #controller 192.0.2.3 role active

(host) [mynode] (HA group information "new") #controller 192.0.2.4 role standby

(host) [mynode] (HA group information "new") #preemption

Related Commands

Command

Description

show ha group

Displays HA profile settings.

show ha ap

Displays profile settings for APs using HA.

show ha heartbeat counters

Displays heartbeat statistics information for HA.

show ha oversubscription statistics

Displays oversubscription statistics information for HA.

Command History

Release

Modification

ArubaOS 8.0.0.0

Command introduced.

Command Information

Platforms

License

Command Mode

All platforms

Base operating system.

Config mode on Mobility Master.

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