All ports are set to auto at both ends. Tried setting it manually on a PC - sure enough, more CRC errors, but the switch also reports "Duplex Mismatch" - which it doesn't do the rest of the time, so that can't be it.
Cables I will check, perhaps swap some ports around to see if the problem stays with PC or cable.
Driver updates - pretty sure already ok, but will double-check again.
Switchport - well, interestingly enough the ports affected are all odd (top row): 9,13,17, 23,29,31,39,47 - so will swap some round to rule this out.
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by: calvinetterPosted on 2007-06-19 at 06:28:55ID: 19315593
If you're getting a lot of CRC errors, then could be 1 of the following:
- duplex mismatch between PC & switch
- bad cable (especially check crimped ends on self-made cables)
- bad NIC or just needs driver update
- bad switchport
Duplex mismatch happens when 1 device is manually set to full-duplex & the other device is set to 'auto' (auto-negotiate). To avoid speed/duplex mismatches: both devices set to 'auto' for duplex & speed, or both set manually to full-duplex & specific speed.
If you suspect cables, also check if they're physically damaged, pinched, sharply-bent, or near a possible source of noise/interference (power lines, flourescent lights, etc).
Most likely is a duplex mismatch or NICs that need a driver update. Sometimes 2 different devices, even if both set to 'auto' won't properly negotiate (ie, you'll see CRC errors, etc). If so, you'll want to set both manually to same speed/duplex.
cheers