Cluster Monitoring

• There are two types of monitoring in a cluster - service monitoring and node monitoring.
• The active node constantly monitors the availability of the service and its resources.
• If the service becomes non-responsive, the active node will initiate a fail-over of the service to the passive node.
• If one of the resources required by the service (e.g. the disks) become in-accessible, the active node will initiate such a fail-over, too.
• The passive node monitors the status of the active node.
• If the passive node sees that the active node is down, it will initiate a fail-over of the service (i.e. try to take over the service).

Originally written by guy keren