en-US/vr-monitor.xml

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<section id="vr-monitor">
  <title>Service Monitoring Tool for Virtual Router</title>
  <para>Various services running on the &PRODUCT; virtual routers can be monitored by using a
    Service Monitoring tool. The tool ensures that services are successfully running until &PRODUCT;
    deliberately disables them. If a service goes down, the tool automatically restarts the VR, and
    if that does not bring up the VR, an alert as well as an event is generated indicating the
    failure.</para>
  <para>Monitoring tool can help to start a VR service, which is crashed due to an unexpected
    reason. For example:</para>
  <itemizedlist>
    <listitem>
      <para>The services crashed due to defects in the source code.</para>
    </listitem>
    <listitem>
      <para>The services that are terminated by the OS when memory or CPU is not sufficiently
        available for the service.</para>
    </listitem>
  </itemizedlist>
  <note>
    <para>Only those services with daemons are monitored. The services that are failed due to errors
      in the service/daemon configuration file cannot be restarted by the Monitoring tool.</para>
  </note>
  <para/>
  <para>The following services are monitored in a VR:</para>
  <itemizedlist>
    <listitem>
      <para>DNS</para>
    </listitem>
    <listitem>
      <para>HA Proxy</para>
    </listitem>
    <listitem>
      <para>SSH</para>
    </listitem>
    <listitem>
      <para>Apache Web Server</para>
    </listitem>
  </itemizedlist>
  <para>The following networks are supported:</para>
  <itemizedlist>
    <listitem>
      <para>Isolated Networks</para>
    </listitem>
    <listitem>
      <para>Shared Networks in both Advanced and Basic zone</para>
    </listitem>
  </itemizedlist>
  <para>This feature is supported on the following hypervisors: XenServer, VMware, and KVM.</para>
</section>