Make sure you review and understand the following descriptions, examples and considerations before setting the Confirm Failover or Block Resource Failover in your LifeKeeper environment. These settings are available from the command line or on the Properties panel in the LifeKeeper GUI.
Confirm Failover On
Definition – Enables manual failover confirmation from System A to System B (where System A is the server whose properties are being displayed in the Properties Panel and System B is the system to the left of the checkbox). If this option is set on a system, it will require a manual confirmation by a system administrator before allowing LifeKeeper to perform a failover recovery of a system that it detects as failed.
Use the lk_confirmso command to confirm the failover. By default, the administrator has ten minutes to run this command. This time can be changed by modifying the CONFIRMSOTO setting in /etc/default/LifeKeeper. If the administrator does not run the lk_confirmso command within the time allowed, the failover will either proceed or be blocked. By default, the failover will proceed. This behavior can be changed by modifying the COMFIRMSODEF setting in /etc/default/LifeKeeper.
Example: If you wish to block automatic failovers completely, you should set the Confirm Failover On option in the Properties panel and also set CONFIRMSODEF to 1 (block failover) and CONFIRMSOTO to 0 (don’t wait to decide on the failover action).
When to select this setting:
This setting is used in most Disaster Recovery, XenServer and other WAN configurations where the configuration does not include redundant heartbeat communication paths.
In a regular site (non-multi-site cluster and non-XenServer), open the Properties page from one server and then select the server that you want the Confirm Failover flag to be set on.
For a Multi-site WAN configuration: Enable manual failover confirmation
For a Multi-site LAN configuration: Do not enable manual failover confirmation
In a multi-site cluster environment – from the non-disaster system, select the DR system and check the set confirm failover flag. You will need to open the Properties panel and select this setting for each non-disaster server in the cluster.
In a XenServer environment, all servers in the list (not just the DR site) need to be checked.
Block Resource Failover On
Definition - By default, all resource failures will result in a recover event that will attempt to recover the failed resource on the local system. If local recovery fails or is not enabled, then LifeKeeper transfers the resource hierarchy to the next highest priority system for which the resource is defined. However, if this setting is selected on a designated system(s), all resource transfers due to a resource failure will be blocked from the given system.
When the setting is enabled, the following message is logged:
Local recovery failure, failover blocked, MANUAL INTERVENTION REQUIRED
Conditions/Considerations:
In a Multi-site configuration, do not select Block Failover for any server in the configuration.
In a XenServer environment, select Block Failover for each system in the cluster.
Remember: This setting will not affect failover behavior if there is a complete system failure. It will only block failovers due to local resource failures.
Setting the Flags on Each Server
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Log in to the LifeKeeper GUI and select a server in your cluster. If the Properties panel option is selected on the View menu, the Properties panel will display (on the right side of the GUI).
On the General tab in the bottom of the panel, your system configuration will be displayed:
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In the Set Confirm Failover On column, select the checkbox for each of the other servers in the cluster.
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In the Set Block Resource Failover On column, select the checkbox for each of the servers in the cluster as required.
IMPORTANT CONSIDERATION FOR MULTI-SITE CLUSTER CONFIGURATIONS: Do not check the Block Resource Failover On fields for the servers in a Multi-Site Cluster configuration.
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Click OK.