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

Manual Operations for Service Group Dependencies

You can manually bring a service group online, take it offline, or fail it over using the hagrp -online, -offline, and -switch commands.

Manual Online

Basic rules governing how to manually bring a service group online also apply to service groups with dependencies. Additionally, the following rules apply for service groups configured with dependencies. For example:

  • For online dependencies, a parent group cannot be brought online manually if the child is not online.
  • For online local dependencies, a parent group cannot be brought online manually on any system other than the system on which the child is online.
  • For online remote dependencies, a parent group cannot be brought online manually on the system on which the child is online.
  • For offline local dependencies, a parent group cannot be brought online manually on the system on which the child is online.

Typically, bringing a child group online manually is never rejected, except under the following circumstances:

  • For online local dependencies, if parent is online, a child group online is rejected for any system other than the system where parent is online.
  • For online remote dependencies, if parent is online, a child group online is rejected for the system where parent is online.
  • For offline local dependencies, if parent is online, a child group online is rejected for the system where parent is online.

The following examples describe situations where bringing a parallel child group online is accepted:

  • For a parallel child group linked online local with failover/parallel parent, multiple instances of child group online are acceptable.
  • For a parallel child group linked online remote with failover parent, multiple instances of child group online are acceptable, as long as child group does not go online on the system where parent is online.
  • For a parallel child group linked offline local with failover/parallel parent, multiple instances of child group online are acceptable, as long as child group does not go online on the system where parent is online.

Manual Offline

Basic rules governing how to manually take a service group offline also apply to service groups with dependencies. Additionally, VCS rejects manual offlining if the procedure violates existing group dependencies. Typically, firm dependencies are more restrictive to offlining a child group while parent group is online. Rules for manual offlining include:

  • Parent group offline is never rejected.
  • For all soft dependencies, child group can be offlined regardless of the state of parent group.
  • For all firm dependencies, if parent group is online, child group offline is rejected.
  • For the online local hard dependency, if parent group is online, child group offline is rejected.

Manual Switch

Switching a service group implies manually taking a service group offline on one system, and manually bringing it back online on another system. Basic rules governing how to manually switch a service group also apply to service group dependencies. Additionally, VCS rejects manual switch if the group does not comply with manual offline or manual online rules described above.

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