HP 5400zl Series Installation And Getting Started Manual page 81

Because the Series 5400zl Switches behave in this way (in compliance
with the IEEE 802.3 standard), if a device connected to the switch has
a fixed configuration at full duplex, the device will not connect correctly
to the switch. The result will be high error rates and very inefficient
communications between the switch and the device.
Ensure that all devices connected to the Series 5400zl Switches are
configured to auto negotiate, or are configured to connect at half duplex
(all hubs are configured this way, for example).
If necessary though, you can modify the configuration of the ports on the
Series 5400zl Switches to match the configuration of the connected
device. Use the switch console, the web browser interface, or ProCurve
Manager to modify the port configuration.
■ Check the port configuration. A port on your Series 5400zl 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 which is on the ProCurve Web site. See
details.
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 ProCurve Networking
Web site in the Reference Library, www.procurve.com/library, in the A-Z index
section.
Troubleshooting
Basic Troubleshooting Tips
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