A security administrator is reviewing the automated failover process for a high-availability cluster to ensure continuous operations during a hardware failure. What is the correct order of steps the cluster system takes when a primary node fails?
- 1The cluster heartbeat service detects a loss of communication from the active primary node.
- 2Fencing mechanisms isolate the unresponsive primary node to prevent split-brain data corruption.
- 3The secondary standby node is promoted to active status and claims the cluster's virtual IP address.
- 4Application services complete initialization on the new active node and begin processing user requests.
Answer
The correct sequence starts with detecting the node failure via heartbeat loss, followed by fencing the primary node to prevent split-brain condition, promoting the secondary node and assigning the virtual IP, and concluding with service initialization and client traffic resumption.
In high-availability clustering, failover must strictly proceed from failure detection (heartbeat loss) to node fencing (isolation), followed by role promotion/virtual IP takeover, and finally service resumption. Fencing must occur before promotion to protect data integrity against split-brain scenarios.
Step-by-Step Solution
Key Concept
High-Availability Automated Failover Sequence and Fencing