<node name="dhcpv6-options">
  <properties>
    <help>DHCPv6 options</help>
  </properties>
  <children>
    <node name="prefix-delegation">
      <properties>
        <help>DHCPv6 Prefix Delegation Options</help>
      </properties>
      <children>
        <leafNode name="length">
          <properties>
            <help>Request IPv6 prefix length from peer</help>
            <valueHelp>
              <format>32-64</format>
              <description>Length of delegated prefix</description>
            </valueHelp>
            <constraint>
              <validator name="numeric" argument="--range 32-64"/>
            </constraint>
          </properties>
        </leafNode>
        <tagNode name="interface">
          <properties>
            <help>Delegate IPv6 prefix from provider to this interface</help>
            <completionHelp>
              <script>${vyos_completion_dir}/list_interfaces.py --broadcast</script>
            </completionHelp>
          </properties>
          <children>
            <leafNode name="address">
              <properties>
                <help>Local interface address assigned to interface</help>
                <valueHelp>
                  <format>&gt;0</format>
                  <description>Used to form IPv6 interface address (default: EUI-64)</description>
                </valueHelp>
                <constraint>
                  <validator name="numeric" argument="--non-negative"/>
                </constraint>
              </properties>
            </leafNode>
            <leafNode name="sla-id">
              <properties>
                <help>Interface site-Level aggregator (SLA)</help>
                <valueHelp>
                  <format>0-128</format>
                  <description>Decimal integer which fits in the length of SLA IDs</description>
                </valueHelp>
                <constraint>
                  <validator name="numeric" argument="--range 0-128"/>
                </constraint>
              </properties>
            </leafNode>
            <leafNode name="sla-len">
              <properties>
                <help>Site-Level aggregator (SLA) length</help>
                <valueHelp>
                  <format>0-128</format>
                  <description>Length of delegated prefix</description>
                </valueHelp>
                <constraint>
                  <validator name="numeric" argument="--range 0-128"/>
                </constraint>
              </properties>
            </leafNode>
          </children>
        </tagNode>
      </children>
    </node>
    <leafNode name="parameters-only">
      <properties>
        <help>Acquire only config parameters, no address</help>
        <valueless/>
      </properties>
    </leafNode>
    <leafNode name="temporary">
      <properties>
        <help>IPv6 "temporary" address</help>
        <valueless/>
      </properties>
    </leafNode>
  </children>
</node>