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If you do not use Hardware Address Takeover, the ARP cache of clients can be updated by adding the clients’ IP addresses to the PING_CLIENT_LIST variable in the /usr/sbin/cluster/etc/clinfo.rc file.
2.4.4 NFS Exports and NFS Mounts
There are two items concerning NFS when doing the configuration of a Resource Group:
Filesystems to Export File systems listed here will be NFS exported, so they can be mounted by NFS client systems or other nodes in the cluster.
Filesystems to NFS mount Filling in this field sets up what we call an NFS cross mount. Any file system defined in this field will be NFS mounted by all the participating nodes, other than the node that is currently holding the resource group. If the node holding the resource group fails, the next node to take over breaks its NFS mount for this file system, and mounts the file system itself as part of its takeover processing.
2.5 Application Planning
The central purpose for combining nodes in a cluster is to provide a highly available environment for
Planning for these applications requires that you be aware of their location within the cluster, and that you provide a solution that enables them to be handled correctly, in case a node should fail. In an HACMP for AIX cluster, these critical applications can be a single point of failure. To ensure the availability of these applications, the node configured to take over the resources of the node leaving the cluster should also restart these applications so that they remain available to client processes.
To put the application under HACMP control, you create an application server cluster resource that associates a