en-US/dedicated-ha-hosts.xml

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<section id="dedicated-ha-hosts">
    <title>Dedicated HA Hosts</title>
    <para>One or more hosts can be designated for use only by HA-enabled VMs that are restarting due to a host failure. Setting up a pool of such dedicated HA hosts as the recovery destination for all HA-enabled VMs is useful to:</para>
    <itemizedlist>
        <listitem><para>Make it easier to determine which VMs have been restarted as part of the &PRODUCT; high-availability function. If a VM is running on a dedicated HA host, then it must be an HA-enabled VM whose original host failed. (With one exception: It is possible for an administrator to manually migrate any VM to a dedicated HA host.).</para></listitem>
        <listitem><para>Keep HA-enabled VMs from restarting on hosts which may be reserved for other purposes.</para></listitem>
    </itemizedlist>
    <para>The dedicated HA option is set through a special host tag when the host is created. To allow the administrator to dedicate hosts to only HA-enabled VMs, set the global configuration variable ha.tag to the desired tag (for example, "ha_host"), and restart the Management Server. Enter the value in the Host Tags field when adding the host(s) that you want to dedicate to HA-enabled VMs.</para>
    <note><para>If you set ha.tag, be sure to actually use that tag on at least one host in your cloud. If the tag specified in ha.tag is not set for any host in the cloud, the HA-enabled VMs will fail to restart after a crash.</para></note>
</section>