HP ProCurve 6400cl Series Management And Configuration Manual page 365

Configuring for Network Management Applications
CDP on the Series 5300xl Switches
CDP-Capable Hubs. Some hubs are capable of running CDP, but also
forward CDP packets as if the hub itself were transparent to CDP. Such hubs
will appear in the switch's CDP Neighbors Table and will also maintain a CDP
Neighbors Table similar to that for switches. For more information, refer to
the documentation provided for the specific hub.
Troubleshooting CDP Operation. Refer to "CDP Problems" and "Using the
.
Event Log To Identify Problem Sources" in Appendix C
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