en-US/vr-monitor.xml

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<section id="vr-monitor">
  <title>Service Monitoring Tool for Virtual Router</title>
  <para>The network service daemons running on the &PRODUCT; virtual routers can be monitored by
    using the Service Monitoring tool. If a service goes down, the tool automatically restarts the
    service, and if that does not help bringing up the service, an event log is written to
      <filename>/var/log/messages</filename> indicating the failure. A new global parameter,
      <code>network.router.enableservicemonitoring</code>, has been introduced to control this
    feature. The default value is true, implies, monitoring is enabled. On changing this parameter,
    you need to restart the Management Server and the virtual router.</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 the 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>
  <para/>
  <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>
    <para>VPC networks are not supported.</para>
  </note>
  <para/>
  <para>The following services are monitored in a VR:</para>
  <itemizedlist>
    <listitem>
      <para>DNS</para>
    </listitem>
    <listitem>
      <para>DHCP</para>
    </listitem>
    <listitem>
      <para>SSH</para>
    </listitem>
    <listitem>
      <para>Apache Web Server</para>
    </listitem>
    <listitem>
      <para>Load balancing service</para>
    </listitem>
  </itemizedlist>
  <para>The following networks are supported:</para>
   <itemizedlist>
    <listitem>
      <para>Isolated Networks</para>
    </listitem>
    <listitem>
      <para>Shared Networks in Advanced zone</para>
    </listitem>
     <listitem>
       <para>Shared Networks in Basic zone</para>
     </listitem>
   </itemizedlist>
  <note>
    <para>VPC networks are not supported.</para>
  </note>
  <para>This feature is supported on all the hypervisors.</para>
</section>