Nortel business policy switch 2000 User Manual page 356

356 Chapter 6 Troubleshooting
The Business Policy Switch negotiates port speeds according to the IEEE 802.3u
autonegotiating standard. The switch adjusts (autonegotiates) its port speed and
duplex mode to match the best service provided by the connected station, up to
100 Mb/s in full-duplex mode as follows:
• If the connected station uses a form of autonegotiation that is not compatible
with the IEEE 802.3u autonegotiating standard, the Business Policy Switch
cannot negotiate a compatible mode for correct operation.
• If the autonegotiation feature is not present or not enabled at the connected
station, the Business Policy Switch may not be able to determine the correct
duplex modes.
In both situations, the Business Policy Switch "autosenses" the speed of the
connected station and, by default, reverts to half-duplex mode. If the connected
station is operating in full-duplex mode, it cannot communicate with the switch.
To correct this mode mismatch problem:
1
Use the Port Configuration screen to disable autonegotiation for the suspect
port (see Chapter 3).
2 Manually set the Speed/Duplex field to match the speed/duplex mode of the
connected station (see Chapter 3).
You may have to try several settings before you find the correct speed/duplex
mode of the connected station.
If the problem persists:
1 Disable the autonegotiation feature at the connected station.
2 Manually set the speed/duplex mode of the connected station to the same
speed/duplex mode you have manually set for the Business Policy Switch
port.
208700-C
Note: Nortel Networks recommends that you manually set the Business
Policy Switch port to the desired speed/duplex mode when you connect
to any of the following Nortel Networks products:
• BayStack 450 product family
• BayStack 410 product family