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New Member

Catalyst 2950 is hanging frequently

Currently, we tried to replace 3com switch with Catalyst 2950.

After we replaced the switch, we encounted a problem.

Catalyst was hanging so frequently...

The switch was connected many 3Com hubs...

So, I thought it was happened for the collision.

Is the switch affected by only collision counts?

Collision counts can stop a switch? I think it is unbelievable because it has never happened when the 3Com switch was connected....

  • Other Network Infrastructure Subjects
New Member

Re: Catalyst 2950 is hanging frequently


At the customer site, we have exactly the same thing, we have replace a switch 3100 by a switch 3550.

Behind the 3550, we have many 3COM hubs.

The switch 3550 with the port which have too collisions are hanging down.

But you have a message like

Error Message ETHCNTR-3-HALF_DUX_COLISION_EXCEED_THRESHOLD: Collision at [chars] exceed threshold. Consider as loop-back.

If You have solution , we are interesting ...

(We have preconize to change the hubs by switchs behind the switch 3550)

It seems to be that switch 3550 or 2950 are too intelligent with collisions and protect theirs ports....


Re: Catalyst 2950 is hanging frequently

Did you hardcode your connections from the 2950 down to the 3Com gear ? This would be the first thing to try to make sure both ends of the link are configured the same and not left to autonegotiate . If you have mismatches the 2950 may be taking down the link to a err-disable state (port shutdown) if it is seeing excess collisions and or port problems .

New Member

Re: Catalyst 2950 is hanging frequently


Thank you for your reply...

I have not made hardcoding that switch...

But not only one port but the all port of the switch are not working..

I can not say it's reason is collision, but anyway, collision is supposed to be a problem.

but, collision can affect to all port of switch? and the switch didn't work properly...

Anyway, I should try what you recommanded...

and if I have sollution, I'll post it...

Thank you...

New Member

Re: Catalyst 2950 is hanging frequently

if the 2950 crashes frequently why not connect a console to check its status or last message ? this might give you some crusial information.

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