en-US/reserved-ip-addresses-non-csvms.xml

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<section id="reserved-ip-addresses-non-csvms">
  <title>IP Reservation in Isolated Guest Networks</title>
  <para>In isolated guest networks, a part of the guest IP address space can be reserved for
    non-&PRODUCT; VMs or physical servers. To do so, you configure a range of Reserved IP addresses
    by specifying the CIDR when a guest network is in Implemented state. If your customers wish to
    have non-&PRODUCT; controlled VMs or physical servers on the same network, they can share a part
    of the IP address space that is primarily provided to the guest network.</para>
  <para>In an Advanced zone, an IP address range or a CIDR is assigned to a network when the network
    is defined. The &PRODUCT; virtual router acts as the DHCP server and uses CIDR for assigning IP
    addresses to the guest VMs. If you decide to reserve CIDR for non-&PRODUCT; purposes, you can
    specify a part of the IP address range or the CIDR that should only be allocated by the DHCP
    service of the virtual router to the guest VMs created in &PRODUCT;. The remaining IPs in that
    network are called Reserved IP Range. When IP reservation is configured, the administrator can
    add additional VMs or physical servers that are not part of &PRODUCT; to the same network and
    assign them the Reserved IP addresses. &PRODUCT; guest VMs cannot acquire IPs from the Reserved
    IP Range.</para>
  <section id="ip-reserve-consider">
    <title>IP Reservation Considerations</title>
    <para>Consider the following before you reserve an IP range for non-&PRODUCT; machines:</para>
    <itemizedlist>
      <listitem>
        <para>IP Reservation is supported only in Isolated networks.</para>
      </listitem>
      <listitem>
        <para>IP Reservation can be applied only when the network is in Implemented state.</para>
      </listitem>
      <listitem>
        <para>No IP Reservation is done by default.</para>
      </listitem>
      <listitem>
        <para>Guest VM CIDR you specify must be a subset of the network CIDR.</para>
      </listitem>
      <listitem>
        <para>Specify a valid Guest VM CIDR. IP Reservation is applied only if no active IPs exist
          outside the Guest VM CIDR. </para>
        <para>You cannot apply IP Reservation if any VM is alloted with an IP address that is
          outside the Guest VM CIDR.</para>
      </listitem>
      <listitem>
        <para>To reset an existing IP Reservation, apply IP reservation by specifying the value of
          network CIDR in the CIDR field.</para>
        <para>For example, the following table describes three scenarios of guest network
          creation:</para>
        <informaltable>
          <tgroup cols="5" align="left" colsep="1" rowsep="1">
            <colspec colnum="1" colname="c1" colwidth="33.0pt"/>
            <colspec colnum="2" colname="c2" colwidth="84.75pt"/>
            <colspec colnum="3" colname="c3" colwidth="97.5pt"/>
            <colspec colnum="4" colname="c4" colwidth="129.0pt"/>
            <colspec colnum="5" colname="c5" colwidth="336.0pt"/>
            <thead>
              <row>
                <entry><para>Case</para></entry>
                <entry><para> CIDR</para></entry>
                <entry><para>Network CIDR</para></entry>
                <entry><para>Reserved IP Range for Non-&PRODUCT; VMs</para></entry>
                <entry><para>Description</para></entry>
              </row>
            </thead>
            <tbody>
              <row>
                <entry><para>1</para></entry>
                <entry><para>10.1.1.0/24</para></entry>
                <entry><para> None</para></entry>
                <entry><para>None</para></entry>
                <entry><para>No IP Reservation.</para></entry>
              </row>
              <row>
                <entry><para>2</para></entry>
                <entry><para>10.1.1.0/26</para></entry>
                <entry><para>10.1.1.0/24</para></entry>
                <entry><para>10.1.1.64 to 10.1.1.254</para></entry>
                <entry><para>IP Reservation configured by the UpdateNetwork API with
                    guestvmcidr=10.1.1.0/26 or enter 10.1.1.0/26 in the CIDR field in the
                  UI.</para></entry>
              </row>
              <row>
                <entry><para>3</para></entry>
                <entry><para>10.1.1.0/24</para></entry>
                <entry><para>None</para></entry>
                <entry><para>None</para></entry>
                <entry><para>Removing IP Reservation by the UpdateNetwork API with
                    guestvmcidr=10.1.1.0/24 or enter 10.1.1.0/24 in the CIDR field in the UI.
                  </para></entry>
              </row>
            </tbody>
          </tgroup>
        </informaltable>
      </listitem>
    </itemizedlist>
  </section>
  <section id="ip-reserv-limition">
    <title>Limitations</title>
    <itemizedlist>
      <listitem>
        <para>The IP Reservation is not supported if active IPs that are found outside the Guest VM
          CIDR. </para>
      </listitem>
      <listitem>
        <para>Upgrading network offering which causes a change in CIDR (such as upgrading an
          offering with no external devices to one with external devices) IP Reservation becomes
          void if any. Reconfigure IP Reservation in the new re-implemeted network.</para>
      </listitem>
    </itemizedlist>
  </section>
  <section id="best-practice-ipreserv">
    <title>Best Practices</title>
    <para>Apply IP Reservation to the guest network as soon as the network state changes to
      Implemented. If you apply reservation soon after the first guest VM is deployed, lesser
      conflicts occurs while applying reservation. </para>
  </section>
  <section id="reserve-ip">
    <title>Reserving an IP Range</title>
    <orderedlist>
      <listitem>
        <para>Log in to the &PRODUCT; UI as an administrator or end user.</para>
      </listitem>
      <listitem>
        <para>In the left navigation, choose Network.</para>
      </listitem>
      <listitem>
        <para>Click the name of the network you want to modify.</para>
      </listitem>
      <listitem>
        <para>In the Details tab, click Edit.<inlinemediaobject>
            <imageobject>
              <imagedata fileref="./images/edit-icon.png"/>
            </imageobject>
            <textobject>
              <phrase>edit-icon.png: button to edit a network</phrase>
            </textobject>
          </inlinemediaobject></para>
        <para>The CIDR field changes to editable one.</para>
      </listitem>
      <listitem>
        <para>In CIDR, specify the Guest VM CIDR.</para>
      </listitem>
      <listitem>
        <para>Click Apply.</para>
        <para>Wait for the update to complete. The Network CIDR and the Reserved IP Range are
          displayed on the Details page.</para>
      </listitem>
    </orderedlist>
  </section>
</section>