The <simpleSteps> element has the following attributes:
executionMode – An optional attribute that indicates whether the contained steps should be executed in a series or in parallel over the target hosts. The legal values are as follows:
PARALLEL
SERIES
If this attribute is omitted, the value is PARALLEL.
limitToHostSet – An optional attribute that specifies the name of the host set that contains the hosts that are considered to be valid targets for this plan.
If this attribute is omitted, all hosts are considered to be valid targets. Otherwise, the targets that you specify must be a subset of the hosts that are contained in the named host set. If the targets include a host that is not contained in the named host set, the plan issues a runtime error. The plan also issues a runtime error if you specify a name that does not correspond to an existing, supported host set. If the specified host set is defined by a plug-in, pluginName must be prefixed to the host set name, such as pluginName#hostSetName. These plan runtime errors are reported during validation before the preflight starts.