HP J4818A Installation And Getting Started Manual page 47

Make sure that all devices connected to the Series 2300 and 2500 switches
are configured to auto negotiate, or are configured to connect at half
duplex (all hubs are configured this way, for example).
Check the port configuration (Series 2500 Switches only). A port
I
on your Series 2500 switch may not be operating as you expect because
it has been put into a "blocking" state by Spanning Tree, GVRP (automatic
VLANs), or LACP (automatic trunking). (Note that the normal operation
of the Spanning Tree, GVRP, and LACP features may put the port in a
blocking state.) Or, the port just may have been configured as disabled
through software.
Use the switch console to determine the port's configuration and verify
that there is not an improper or undesired configuration of any of the
switch features that may be affecting the port. See the Management and
Configuration Guide that came with your Series 2500 switch for more
information.
For more information on possible network problems and their solutions, refer
to the technical note "Troubleshooting LAN Performance and Intermittent
Connectivity Problems", which can be found on the HP ProCurve web site,
http://www.hp.com/go/hpprocurve under the
Troubleshooting
Basic Troubleshooting Tips
button.

           
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