10.5 High Availability: Running iManager in a Clustered Environment

Although iManager is a session-based tool that ships without any failover features, you can run it in a clustered environment. For more information about clustering, see the OES Clustering documentation.

  1. Install and configure iManager on the nodes in the cluster where the virtual IP is moved to (that is, an Active/Active cluster).

    If the node running iManager fails, Novell Cluster Services detects the node failure and moves (reloads) the virtual IP address on another node in the cluster.

  2. Using the Generic_IP_Service template that ships with Novell Cluster Services, create a new cluster resource called iManager.

    This cluster resource uses a virtual IP address that moves between nodes in the cluster. When creating a new cluster resource, the wizard steps you through the creation of a load script and an unload script.

  3. Verify the load and unload scripts.

    The load script should contain only the following lines (any other lines should be commented out):

    . /opt/novell/ncs/lib/ncsfuncs
    exit_on_error add_secondary_ipaddress xxx.xxx.xxx.xxx
    exit 0

    The unload script should contain only the following lines (any other lines should be commented out):

    . /opt/novell/ncs/lib/ncsfuncs
    ignore_error del_secondary_ipaddress xxx.xxx.xxx.xxx
    exit 0
  4. Browse to the iManager URL.

iManager services are now highly available. However, any live sessions are not failed over. If a service fails in the middle of user operations, users must reauthenticate and restart whatever operations were interrupted.

Because iManager and Tomcat are already running (Active/Active) on the other nodes, there is no load time for these applications if Novell Cluster Services has to migrate (move) the virtual IP to another node.

There is little benefit in using an Active/Passive cluster because it requires much more configuration and makes you wait the entire load time for each failover. If you really want iManager configured as an Active/Passive clustered resource, you must create a cluster resource that loads and unloads iManager and its dependencies (such as Tomcat). This identical configuration of iManager then needs to be done on all nodes where you want iManager highly available.