From where the errors come from...

[TheGreatDoc]

Hi NFS Pro Dudes,

Im saying for a time big peaks of errors on some ports of my switches.

How can I debug from where the errors come from and what is causing them?

[SimonV]

What sort of errors are you seeing exactly?

[TheGreatDoc]

Graphed by cacti from default interface errors/discards template.

[deanwebb]

If you could post the errors, we could take a look at them. Just modify machine names and IP addresses if those would reveal anything that shouldn't be revealed, and we'll look at them.

[TheGreatDoc]

If you could post the errors, we could take a look at them. Just modify machine names and IP addresses if those would reveal anything that shouldn't be revealed, and we'll look at them.

And that is exactly my question. Where can i look further than a "show interface"?

[srg]

What platform is this? (this kind of counters are often very platform specific)

[TheGreatDoc]

Its a Cisco C3750. But as far I can see, the errors showed in graph are not in the "show interface" command.....

[GeorgeS]

play a bit with the show controller command, i am a bit busy this morning and do not have the time to find  a c3750 in our network.  sh controller ethernet (something) should be what are you looking. 

[dlots]

Errors come mostly from duplex mismatches and bad cables in my experiance

[TheGreatDoc]

The thing is that the errors/discards are not constant and the dont come in the heavy traffic timeline.

[icecream-guy]

The thing is that the errors/discards are not constant and the dont come in the heavy traffic timeline.

It could also be EMF radiation, e.g. cables are run too close to fluorescent lights, so when someone goes and turns a light on, someone else network becomes slow.   

I've seen this when I worked in a large warehouse where the network cables were run up in the top of the warehouse along with the lighting and electrical with wires run down around electrical conduit to the workstations...and they wondered why the network was slow...

[matgar]

Its a Cisco C3750. But as far I can see, the errors showed in graph are not in the "show interface" command.....

You could give this a try.

Code Select Expand


sh controllers ethernet-controller GigabitEthernet x/y/z


I also found this list of commands for trouble shooting links.

Code Select Expand


Show interface status | inc connected
Test cable-diagnostics tdr interface <>
Show cable-diagnostic tdr interface <>
Show interface <>
Show interface <> counters
Show interface <> counters errors
Show interface counter errors
Show controller Ethernet-controller <>
Show platform pm if-numbers
Show controllers Ethernet-controller port-asic statistics
Show platform port-asic stats drop <>