How to Configure Failover Functionality

How to Configure Failover Functionality

Summary 

This Knowledgebase article provides information about how to configure failover functionality.

More Information 

The Primary and Secondary servers in a Neverfail pair are continuously connected via the Neverfail Channel. When the Active server becomes unresponsive due to a hardware crash, lost of network connection, or a power outage, the passive server can initiate a failover.

Procedure

The time interval for missed heartbeats can be changed using the Neverfail Heartbeat Management Client. The default value is 60 seconds. By default, if a heartbeat is missed for more than 60 seconds, the server group can initiate a failover. Adjusting the value for missed heartbeats should be carefully changed as it can affect the server group's functionality.
Example:
  • Setting the timeout value for missed heartbeats to a high value will increase the time interval before a failover.  As a result, the active server might stay unavailable too long before the passive server initiates the failover process.
  • Setting the timeout value for missed heartbeats to a low value for a server pair that has low channel bandwidth, may cause a split-brain syndrome.
To enable or disable automatic failovers initiated by the passive server, perform the following steps:
  1. From the Neverfail Advanced Management Client, select the Server: Monitoring tab.
  2. Click the Failover button.
  3. Clear the following check boxes:
    • Failover from Primary server to Secondary server if channel heartbeat is lost for failover timeout.
    • Failover from Secondary server to Primary server if channel heartbeat is lost for failover timeout.
  4. Click OK.

Applies To

All Versions
Related Information

None

 

KBID-794 


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