freeware packet sniffer

[EricF]

I'm looking for a good packet sniffing tool, preferably freeware, so I can find out which NIC (or jetdirect card) is suffering from packet loss so i don't have to power off each unit to see if things get better.

I'm guessing it's either a bad jetdirect or the 17yr old switch is coming up on its last legs.

I've had 2 jetdirect cards go out, literally OUT at the same time. Replaced those and they're working again.
And 1 of the printers yesterday started to print half sheets of paper, scramblings, sometimes nothing. they replaced the printer (using the same jetdirect) and the problem is OK, but it was OK for a week after I replaced 2 jetdirects.
I'm guessing the switch is starting to go out. There PC's are fine though...

any ideas on a good sniffing tool?

 

[wwillson]

Wireshark is fantastic...

 

[BobFout]

Yup, I've used Ethereal/Wireshark for years.

 

[bepperb]

We also use it at work.

 

[OVERKILL]

I assume the switch is not high-end enough to provide you with this sort of information at the console level?

Ethereal is great.

 

[BobFout]

Originally Posted By: OVERK1LL
I assume the switch is not high-end enough to provide you with this sort of information at the console level?

Ethereal is great.


True, most switches will at least show you errors, jabbers, malformed frames, etc.

 

[javacontour]

Solaris/openSolaris has snoop built in that will capture and ethernet frames on the network, as well as give you information about many of the protocols such as ARP/RARP RPC, etc.

So you can get as low level and in some cases, as high level as you wish.

 

[EricF]

The switch is nothing to write home about.. it's a centercom.

wireshark worked remarkably well! thank you all for the advice!