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Product: Cluster Server Guides   
Manual: Cluster Server 4.1 User's Guide   

Dependencies in Failover and Parallel Service Groups

In the following sections the term "instance" applies to parallel groups only. If a parallel group is online on three systems, an instance of the group is online on each system. For failover groups, only one instance of a group is online at any time.

The following information describes situations in which a child group faults in all service group dependencies with failover and parallel groups.

Failover Parent/Failover Child

online local soft  Failover parent group soft depends on failover child group being online on the same system.

Parent can be brought online on a system, for example, System A, only if the child is online on System A.

    Checkmark  If the child faults, the parent is not taken offline. After the child successfully fails over to another system, for example, System B, VCS migrates the parent to System B. If the child cannot fail over, the parent remains online on System A.

    Checkmark  If parent faults on System A, child remains online on System A. Parent cannot fail over anywhere.

online local firm  Failover parent group firm depends on failover child group being online on the same system.

Parent can be brought online on a system, for example, System A, only if the child is online on System A.

    Checkmark  If the child faults, the parent is taken offline on System A. When a child successfully fails over to another system, for example System B, VCS migrates the parent to System B. If child cannot fail over, parent remains offline.

    Checkmark  If parent faults on System A, child remains online on System A. Parent cannot fail over anywhere.

online local hard Failover parent group firm depends on failover child group being online on the same system.

Parent can be brought online on a system, for example, System A, only if the child is online on System A.

    Checkmark  If the child faults, the parent is taken offline on System A. When a child successfully fails over to another system, for example System B, VCS migrates the parent to System B. If child cannot fail over, parent remains offline.

    Checkmark  If parent faults on System A, child is taken offline on System A. When child successfully fails over to System B, VCS migrates the parent to System B. If child cannot fail over, child continues to run on System A.

online global soft  Failover parent group soft depends on failover child group being online anywhere in the cluster. Parent can be brought online as long as a child group is running somewhere in the cluster.

    Checkmark  If the child faults, the parent remains online when the child faults and fails over. The parent also remains online when the child faults and cannot fail over.

    Checkmark  If parent faults on System A, child remains online on System A. Parent fails over to next-available system. If no system is available, the parent remains offline.

online global firm   Failover parent group firm depends on failover child group being online anywhere in the cluster.

Parent can be brought online as long as a child group is running somewhere in the cluster. For example, the parent group is online on System A, and the child group is online on System B.

    Checkmark  If the child faults on System B, the parent group on System A is taken offline. When the child successfully fails over to another system, for example, System C, the parent group is brought online on a suitable system. If child group cannot fail over, parent group remains offline.

    Checkmark  If parent faults on System A, child remains online on System A. Parent fails over to next-available system. If no system is available, the parent remains offline.

online remote soft  Failover parent group soft depends on failover child group being online on any other system in the cluster.

Parent can be brought online on any system other than the system on which the child is online. For example if child group is online on System B, the parent group can be online on System A.

    Checkmark  If the child faults on System B, the parent remains online on System A unless VCS selects System A as the target system on which to bring the child group online. In that case, the parent is taken offline. After the child successfully fails over to System A, VCS brings the parent online on another system, for example System B. If the child faults on System A, the parent remains online on System B unless VCS selects System B as the target system.

online remote firm   Failover parent group firm depends on failover child group being online on any other system in the cluster.

Parent can be brought online on any system other than the system on which the child is online. For example if child group is online on System A, the parent group can be online on System B.

    Checkmark  If the child faults on System A, the parent is taken offline on System B. After the child successfully fails over to another system, VCS brings the parent online on a system other than B where the child is also offline. If no other system is available and if the child is offline on System B, the parent is restarted on System B.

    Checkmark  If the parent faults on System A, the child remains online on System B. The parent on System A fails over to a system other than A or B. If no system is available, the parent remains offline.

offline local  Failover parent group depends on failover child group being offline on the same system and vice versa.

Parent can be brought online on any system as long as the child is not online on the system, and vice versa. For example, if child group is online on System B, the parent can be brought online on System A.

    Checkmark  If the child faults on System B, and if VCS selects System A as the target on which to bring the child online, the parent on System A is taken offline and the child is brought online. However, if child selects System C as the target, parent remains online on System A.

    Checkmark  If parent faults, child remains online. If there is no other system to which parent can fail over, parent remains offline.

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Product: Cluster Server Guides  
Manual: Cluster Server 4.1 User's Guide  
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