On which nodes in a Serviceguard cluster is the cmcld daemon required to run?
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on only on node
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all nodes
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on atleast two nodes
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optinal for cluster less than four nodes
The cmcld (cluster membership daemon) must run on all nodes in a Serviceguard cluster. It monitors node status, communicates membership changes, and ensures all nodes agree on cluster composition. Running it only on some nodes would break cluster integrity and communication.
The cmcld (cluster daemon) is the core Serviceguard process responsible for cluster membership, heartbeat monitoring, and failover decision-making, and it must run on every node that is a member of the cluster — not just some or one — because each node needs to independently monitor cluster health and participate in quorum/heartbeat protocols. If cmcld were missing on any node, that node couldn't properly detect failures or participate in cluster decisions, undermining the whole high-availability design. So 'all nodes' is correct; restricting it to one node, two nodes, or making it conditional on cluster size contradicts how Serviceguard's membership protocol is designed to work.