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New Member

Packet Errors & Collisions


The packet errors & collisions on a particular port on my Cat4006 keeps increasing. This is connected to a 4700series router. What can i do to find out the cause of this errors? Thanks


Re: Packet Errors & Collisions

Probably caused by one of the following (or both):

- Duplex mismatch (verify correct duplex setting on switch and router)

- Cable problems (try using a known good cable)


New Member

Re: Packet Errors & Collisions

Initially the problem is at eth1, so i switched the port at the Cat4006 to another port and error still exist.

Next i tried to configure eth0, but again the problem exist.

2 different cables are used. Could the problem lies with other things such as faulty client's NIC?



Re: Packet Errors & Collisions

Bad or faulty NICs can also be a cause but I did not mention it

anymore in my post because you said that it is connected to a

router. Well, it could also be that the ethernet ports on the

router is the cause but I think that's very rare.

So do you see the error on both end of the link?

Is it increasing rapidly?

New Member

Re: Packet Errors & Collisions

yes, both the switchport and router eth have the errors... the collisions are increasing at abt 10-40 per second during peak hours... but so far no complains abt the network is slow or watever. That's the main line out of the company.

i also notice... for the router, only the collision is increasing and not the packet errors (remain at 0)... for the switchport, the collision and output errors are increasing with same values...

New Member

Re: Packet Errors & Collisions

I would bet the switch is set for full duplex, while your router is only doing half, or vice versa. Check if any of the ports are manually configured out of default state.

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