en-US/resizing-volumes.xml

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<section id="resizing-volumes">
  <title>Resizing Volumes</title>
  <para>&PRODUCT; provides the ability to resize data disks; &PRODUCT; controls volume size by using
    disk offerings. This provides &PRODUCT; administrators with the flexibility to choose how much
    space they want to make available to the end users. Volumes within the disk offerings with the
    same storage tag can be resized. For example, if you only want to offer 10, 50, and 100 GB
    offerings, the allowed resize should stay within those limits. That implies if you define a 10
    GB, a 50 GB and a 100 GB disk offerings, a user can upgrade from 10 GB to 50 GB, or 50 GB to 100
    GB. If you create a custom-sized disk offering, then you have the option to resize the volume by
    specifying a new, larger size. </para>
  <para>Additionally, using the resizeVolume API, a data volume can be moved from a static disk
    offering to a custom disk offering with the size specified. This functionality allows those who
    might be billing by certain volume sizes or disk offerings to stick to that model, while
    providing the flexibility to migrate to whatever custom size necessary. </para>
  <para>This feature is supported on KVM, XenServer, and VMware hosts. However, shrinking volumes is
    not supported on VMware hosts.</para>
  <para>Before you try to resize a volume, consider the following:</para>
  <itemizedlist>
    <listitem>
      <para>The VMs associated with the volume are stopped.</para>
    </listitem>
    <listitem>
      <para>The data disks associated with the volume are removed.</para>
    </listitem>
    <listitem>
      <para>When a volume is shrunk, the disk associated with it is simply truncated, and doing so
        would put its content at risk of data loss. Therefore, resize any partitions or file systems
        before you shrink a data disk so that all the data is moved off from that disk.</para>
    </listitem>
  </itemizedlist>
  <para>To resize a volume:</para>
  <orderedlist>
    <listitem>
      <para>Log in to the &PRODUCT; UI as a user or admin.</para>
    </listitem>
    <listitem>
      <para>In the left navigation bar, click Storage.</para>
    </listitem>
    <listitem>
      <para>In Select View, choose Volumes.</para>
    </listitem>
    <listitem>
      <para>Select the volume name in the Volumes list, then click the Resize Volume button <inlinemediaobject>
          <imageobject>
            <imagedata fileref="./images/resize-volume-icon.png"/>
          </imageobject>
          <textobject>
            <phrase>resize-volume-icon.png: button to display the resize volume option.</phrase>
          </textobject>
        </inlinemediaobject></para>
    </listitem>
    <listitem>
      <para>In the Resize Volume pop-up, choose desired characteristics for the storage.</para>
      <mediaobject>
        <imageobject>
          <imagedata fileref="./images/resize-volume.png"/>
        </imageobject>
        <textobject>
          <phrase>resize-volume.png: option to resize a volume.</phrase>
        </textobject>
      </mediaobject>
      <orderedlist numeration="loweralpha">
        <listitem>
          <para>If you select Custom Disk, specify a custom size.</para>
        </listitem>
        <listitem>
          <para>Click Shrink OK to confirm that you are reducing the size of a volume. </para>
          <para>This parameter protects against inadvertent shrinking of a disk, which might lead to
            the risk of data loss. You must sign off that you know what you are doing.</para>
        </listitem>
      </orderedlist>
    </listitem>
    <listitem>
      <para>Click OK.</para>
    </listitem>
  </orderedlist>
</section>