10.5 Logical host use in a non-cluster environment

A logical host is a logical server environment that acts as the execution environment when you run JP1 in a cluster system. Running JP1 on a logical host typically involves linking with cluster software in the cluster system, and performing failover on a logical host basis.

However, by allocating space on the disk and a dedicated IP address to the logical host, and setting it up as a logical host for JP1, you can create a logical host environment that is not linked to the cluster software and is not subject to failover.

By setting up separate instances of JP1 on each logical host, you can start and run multiple instances of JP1 concurrently on a single server.

You can use logical hosts that do not fail over in system configurations similar to the following:

Using multiple instances of JP1 to handle separate applications

[Figure]

When you run more than one application on a single host, the operation of each application can be managed separately in a dedicated logical host.

Using JP1 programs designed for physical hosts in a cluster configuration where the logical host name must match the physical host name

[Figure]

In some cluster systems, the logical host name must be the same as the physical host name (the host name displayed by the hostname command). In this kind of configuration, you cannot run JP1/AJS3 in a physical host environment. Therefore, if you want to do things such as run JP1/AJS3 or monitor logs such as the syslog on each server, do so from the logical host on each server that will not fail over. Note, however, that the logical hosts that do not fail over must have different names from the physical hosts. Note, however, that if a logical host name is the same as the physical host name (the host name displayed by the hostname command), you cannot use the queueless job execution facility or the definition pre-check function.

For further information about setting up and running logical hosts in a non-cluster environment, see the JP1/Base User's Guide.

Organization of this section

To Page Top