192.168.1.10 www.example.com www

dn: cn=www.example.com,ou=Hosts,dc=NIS,dc=Example,dc=com
objectClass: device
objectClass: ipHost
ipHostNumber: 192.168.1.10
cn: www.example.com
cn: www

<source name="hosts">

    <connection-name>NIS</connection-name>

    <field name="cn"/>
    <field name="ipHostNumber" primaryKey="true"/>

    <parameter>
      <param-name>objectClasses</param-name>
      <param-value>ipHost</param-value>
    </parameter>
    <parameter>
      <param-name>base</param-name>
      <param-value>hosts.byaddr</param-value>
    </parameter>

</source>

<entry dn="cn=...+ipHostNumber=...,ou=Hosts,dc=NIS,dc=Example,dc=com">

    <entry-class>org.safehaus.penrose.nis.directory.NISEntry</entry-class>

    <oc>device</oc>
    <oc>ipHost</oc>

    <at name="cn" rdn="true">
      <expression>
import java.util.*;
if (h.cn instanceof Collection) {
    return h.cn.iterator().next();
}
return h.cn;
      </expression>
    </at>
    <at name="cn">
      <variable>h.cn</variable>
    </at>
    <at name="ipHostNumber" rdn="true">
      <variable>h.ipHostNumber</variable>
    </at>

    <source alias="h">
      <source-name>hosts</source-name>
      <field name="cn">
        <variable>cn</variable>
      </field>
      <field name="ipHostNumber">
        <variable>ipHostNumber</variable>
      </field>
    </source>

</entry>