RE: Weird networking issue.

By nature, a hub is half-duplex - it’s a repeater.

Besides, misconfigured duplex will not cause CRC errors.


Heh. Tell that to my Catalyst 3548's and the E250's at the other end. :wink:

Lab testing showed serious throughput issues though (expected) in
duplex-mismatched links, and large increases in runt and mutli-collision
counters. CRC errors and FCS errors also rose in proportion to relative
link saturation in a more simplistic 6500 <->7509<-> 3548 test

Sun's hme cards won't go full duplex even though they advertise it to
remote switch, causing immense headaches to anyone with Sun gear...


That is just not true. I've had several Sun boxes with hme interfaces
properly autoneg into 100/full with misc equipment, including 3548:s, and
working properly.

Yes it will. It will cause CRC errors/RX underflows/RX frags/RX align on
one end and late collissions on the other end depending on which one is
running half duplex and which one is running full duplex.

The behavior I've seen in the past is Sun gear negotiating properly when plugged into Cisco gear that is already running. If you power cycle the switch with the servers already attached the port will not negotiate correctly... usually to half duplex.

Also I've seen duplex problems in the past week that caused, runts, giants, collisions, CRCs, errors of all sorts, kernel module reloads, vlan tagging failure, and depletion of the ozone layer. Or maybe is was reality tv that caused that ozone thing...