component limitToHostSet attribute

The "limitToHostSet" attribute of the <component> element specifies the name of the host set containing the hosts that are considered valid targets for this plan. If unspecified, all hosts are considered valid targets. Otherwise, the targets specified by the client must be a subset of the hosts contained in the named host set. If the targets include a host not contained in the named host set, it is a plan run time error. It is also a plan run time error to specify a name that does not correspond to an existing host set. The plan run time errors described here are reported as preflight errors.

There are two main differences between the platform and the limitToHostSet attributes. First, the platform names one of the predefined platform host sets, whereas the limitToHostSet names a user-defined host set. Accordingly, if the client wants to limit installation based on a custom host set, they should use "limitToHostSet". Secondly, when a component is targeted at a virtual host, the limitToHostSet is tested against the virtual host, whereas the platform is tested against the root physical host of that virtual host. Accordingly, setting a limitToHostSet but no platform allows a component to be installed on a particular set of virtual hosts that might reside on different physical platforms (as is the case with WebLogic applications). Setting a platform but no limitToHostSet allows a component to be installed on any host that is rooted by a physical host with the given platform. Setting both allows one to constraint both degrees.