Controlling Redundancy

After the redundancy feature has been configured and is enabled, you can control its behavior using the redundancy control commands:

• redundancy control set-preferred-site – Updates the preferred site. Effective as soon as it is entered. Does not require a redundancy restart.
• Three options are available: none, site-a, site-b.
• redundancy control start – Activates redundancy feature. If successful, data replication/resource monitoring will start.
• redundancy control stop – Stops the redundancy feature. Replication, monitoring and failover functions are all stopped.
Important:
• Stopping redundancy will stop data replication. Data will be stored to the data store on the active site only.
• Redundancy feature can be stopped on both sites by running redundancy control stop command on a site only.
• However, the redundancy feature must be stopped by manually rerunning redundancy control stop command again on the remaining site if a site is in shutdown or unreachable while stopping the redundancy feature process.
• Do not force reboot/shutdown Skylight orchestrator while stopping redundancy feature process.
• redundancy control restart – Equivalent to entering the start and stop commands. If you change the redundancy configuration, you must enter the restart command.
• redundancy control switch – Switches the active site (from the site that is currently active to the site that is currently passive). If a manual switch is initiated, the Preferred-site option will be automatically set to none.
• redundancy control suspend – This command puts the redundancy features completely on hold:
• It disables failover (automatic and manual).
• It stops replication and monitoring immediately.
• Failover will not occur regardless of the conditions.
To re-enable replication, monitoring and automatic failover, you must enter the resume command. The suspend command is typically used to temporarily put the redundancy feature on hold. For example, during a maintenance window, when you need to reboot an appliance or apply a patch to the operating system.

• redundancy control resume – Re-enables automatic failover after the suspend command was executed.
• redundancy control handle-split-brain – Handling data cannot synchronize between two sites issue.

All commands are run from the appliance console. See Accessing the Appliance Console.