datacollection-config.xml
      <group name="ucd-test" ifType="ignore">
        <mibObj oid=".1.3.6.1.4.1.2021.8.1.100.1" instance="0" alias="openSockets" type="integer"/>
        <mibObj oid=".1.3.6.1.4.1.2021.8.1.100.2" instance="0" alias="openFiles" type="integer"/>
      </group>
      ......
      <systemDef name="Net-SNMP (TEST)">
        <sysoidMask>.1.3.6.1.4.1.2021.</sysoidMask>
        <collect>
          <includeGroup>ucd-test</includeGroup>
        </collect>
      </systemDef>

snmp-graph.properties
reports=  .... snip snip, netsnmp.ucdtest

#Custom Test
report.netsnmp.ucdtest.name=OpenSockets OpenFiles
report.netsnmp.ucdtest.columns=openSockets,openFiles
report.netsnmp.ucdtest.type=node
report.netsnmp.ucdtest.command=--title="Open Sockets/ Open Files" \
 DEF:openSockets={rrd1}:openSockets:AVERAGE \
 DEF:openFiles={rrd2}:openFiles:AVERAGE \
 LINE2:openSockets#000000:"Open Sockets" \
 GPRINT:openSockets:AVERAGE:" Avg  \\: %8.2lf %s" \
 GPRINT:openSockets:MIN:"Min  \\: %8.2lf %s" \
 GPRINT:openSockets:MAX:"Max  \\: %8.2lf %s\\n" \
 LINE2:openFiles#cc0000:"Open Files" \
 GPRINT:openFiles:AVERAGE:"Avg  \\: %8.2lf %s" \
 GPRINT:openFiles:MIN:"Min  \\: %8.2lf %s" \
 GPRINT:openFiles:MAX:"Max  \\: %8.2lf %s\\n"