If auto-negotiation fails, your server can match the line speed
of its link partner.
However, the adapter cannot sense the duplex mode. The server will default
to half duplex, which can result in a duplex mismatch.
Duplex mismatch
The following is an example of a duplex
mismatch: Your iSeries™, configured
for full duplex, is connecting to a hub configured for half duplex. The iSeries server
begins sending information to the hub, which is waiting to receive. When
the receive line is clear, the hub will then begin transmission back to the iSeries server.
During this transmission, the iSeries receives the incoming data and
(if it has data ready) begins transmitting to the hub. Because the hub is
half duplex, it will see this unexpected receipt of data and will cancel the
transmission in progress. This is called a collision. A duplex mismatch problem
might be reported as a 'failure to connect' error, or it might cause a more
subtle performance problem due to intermittent cancelled frames.