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10.2. Clones - Resources That Get Active on Multiple Hosts

Clones were initially conceived as a convenient way to start multiple instances of an IP address resource and have them distributed throughout the cluster for load balancing. They have turned out to quite useful for a number of purposes including integrating with the Distributed Lock Manager (used by many cluster filesystems), the fencing subsystem, and OCFS2.
You can clone any resource, provided the resource agent supports it.
Three types of cloned resources exist:
Anonymous clones are the simplest. These behave completely identically everywhere they are running. Because of this, there can be only one copy of an anonymous clone active per machine.
Globally unique clones are distinct entities. A copy of the clone running on one machine is not equivalent to another instance on another node, nor would any two copies on the same node be equivalent.
Stateful clones are covered later in Section 10.3, “Multi-state - Resources That Have Multiple Modes”.

Example 10.4. A clone of an LSB resource

<clone id="apache-clone">
    <meta_attributes id="apache-clone-meta">
       <nvpair id="apache-unique" name="globally-unique" value="false"/>
    <primitive id="apache" class="lsb" type="apache"/>

10.2.1. Clone Properties

Table 10.2. Properties of a Clone Resource

Field Description
A unique name for the clone