Best way to find a suspected faulty nic

[LizardKing]

My google skills have failed me here!

Is there a easy way to monitor a network for a suspected faulty NIC? we are having random slowdowns on the network that could point to a rogue nic flooding/screwing the network.

Thanks

 

[s0ck]

What kinda slowdowns?

 

[LizardKing]

What kinda slowdowns?

I'm going off third hand info as i've not had chance to have a proper look, but i'm under the impression its latency or lost packets.

I'm just trying to look at all the angle's before the site visit.

 

[morfmedia]

Worth checking whether its set to auto / forced speed, this often causes issues.....

 

[s0ck]

Check which switch is going nuts

 

[Stolly]

Check for ethernet errors on the switch.

I've found int he past that "network slowdowns" in the past are very often caused by all sorts of things higher in the stack than the hardware....

AV software
Malware scanners
Backup software
DNS problems

to name but a few.

 

[drak3]

Worth checking whether its set to auto / forced speed, this often causes issues.....

Common problem.

 

[Nikumba]

Also run wireshark on a laptop so you can see all the data being thrown about the network, we use this in conjuction with the firewall and switches to diagnose network faults

 

[LizardKing]

Wireshark is one of the options, unfortunately the network has the potential of 50+ nics that need to be tested! So looking at each machine individually will be the last resort. The problem is intermittent just to add that extra bit of fun!
Will be looking at the usual suspects (av, malware, dns etc)

 

[PistolPete]

Managed switches??? If so, then look at the port utilisations and the one flooding will show a large increases in packet throughput. Might help ou to only have to look at a switch or 3 to show a place to start