Slowdown on Cisco Switch

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Hello Everyone,

I'm a total noob with switches. A remote location is experience a local slowdown on systems connected to a Cisco 3500 series switch.
The admin there suspects that a nic on one of the systems might be defective and chatty therefore causing the slowdown.
Is there a command for the switch that would show the traffic accross each port to help narrow down the culpret?
Or is there a better way to find a chatty NIC on the network?
Microsoft's Network monitor perhaps?

 

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Protocol analyzer.

 

As BM said, a protocol analyzer will provide a huge amount of info, although experience is needed to make effective use of the output.

Some quick switch commands to check include:

show int <-- check for various errors, a quick filter would be sh int | inc Eth|error

show proc cpu hist <-- check for excessive cpu usage

show ip traff <-- look for drops and errors

And also check the switch log/syslog/snmp for any info.

Again, experience is key in understanding what the outputs indicate.

Spice_Weasel

 

Thanks Guys.
I used Microsoft's network monitor to look for excessive broadcasts. But found nothing major. I'm not totally convicnced it's a switch issue.
I will give those commands a try. Thanks!
I love how network stuff happens on day 1 of my IT Managers (Net Admin) extended leave!

 

How chatty is chatty? I'm showing 3 systems with over 300 broadcasts in about 5 minutes.
Is that pretty normal?

 

Another possibility is the auto-negotiation failing. Particularly half/full duplex when talking to non-Cisco gear. This has bitten me many times.

The usual fix is to nail it at both ends to the correct duplex setting.

Harry.

 

I would think you could use IP accounting as well to see which ip is talking.