Layer 2 Traceroute

[DanielBowen]

Does anybody know a tool, simillar to traceroute that can be run on a Windows machine that will include all layer 2 hops as well as layer 3 hops?

Daniel,

 

[jimbopalmer]

This will be a challenge, in general, as the Hubs and Switches are both 'Quiet' and 'Transparent' devices, unlike Routers who 'discover' each other, and alter the packet being transfered. As far as Vendor Specific solutions both 3com and Nortel have LAN mapping and control software free (3com Network Supervisor and Optivity Switch Manager)but they tend to only find their own gear. The one thing you can't give for your heart's desire is your heart. - Lois McMaster Bujold

 

[DanielBowen]

Do you know of any commands that can be entered. What I am trying to do is discover what switch a workstation is plugged into from the workstation.

Thanks,

 

[jimbopalmer]

I can tell you how I do that, but you will HATE my method.

First, I find the DNS Name, IP or MAC address of my workstation. (I tend to use my DNS server for the IP, then ask my Router for the MAC, but what ever works for you.)

My Router (a Nortel Passport 1200, usually) will tell me which port a given MAC address is on, then I telnet into the switch on that port (often a Nortel baystack 450) and use it's MAC address table to find which port my MAC address is on.

Naystack 450 MAC Address Table

Aging Time: [ 300 seconds ]
Find an Address: [ 00-00-00-00-00-00 ]
Fast Aging: [ Enabled ]



00-80-A2-6B-35-91 Unit: 5 Port: 7
00-80-C0-E1-DB-E3 Unit: 6 Port: 23
00-81-02-3A-6C-42 Unit: 2 Port: 14
00-81-02-3A-6C-D0 Unit: 2 Port: 8
00-81-02-67-F6-AC Unit: 1 Port: 21
00-81-02-69-74-0D Unit: 5 Port: 24
00-81-02-69-76-E1 Unit: 6 Port: 4
00-81-02-6E-51-C7 Unit: 1 Port: 22
00-81-02-BD-82-67 Unit: 1 Port: 8
00-81-02-BD-A1-37 Unit: 4 Port: 6
00-81-02-BD-A5-D8 Unit: 1 Port: 11
00-81-02-C3-A6-44 Unit: 1 Port: 6
00-81-02-C7-76-4A Unit: 4 Port: 4


You should be able to do all this with SNMP, but I find telnet works everywhere, while my network management software is at my desk. The one thing you can't give for your heart's desire is your heart. - Lois McMaster Bujold

 

[MWM]

If you cannot query managed devices with manufacturer-provided software, then you may be looking at 3rd party software.

But before buying it, go to the bank and see about a loan: you may need it.

There is wonderful software from Fluke, especially some made for their tools. Seriously, it is excellent. But their Network Inspector starts at about $2,000 and some versions go to $6,000. If you have their $13,000 Optiview, you're all set.

Tip: some 3rd party software is available for limited time demo use, and may have the functionality you need for the moment (and, if so, you may get the boss to buy it later). Try Network Instruments Observer or Fluke Network Inspector.

Yours,
Mike

 

[ChrisAC]

Or, you could of course just keep records of what is patched in where! If not just go to the comms cab and trace the patch cable from the patch panel to the switch port. It's low tech I know but it's so easy to keep records!

Another option is a layer 1 management system like Patchview. This is basically a database of physical connections that provides a graphical front end so that you can see what is connected to what. It's pretty neat! However, it does require changing all your patch panels to RiT panels and it can be a BIG project! Did one earlier this year .. NIGHTMARE!!

Chris.

 

[MWM]

Yes, even basic physical records (papyrus would work) can ease the inevitable confusion surrounding moving or troubleshooting links. I have yet to see a complete and current set of records, but even a few basic notes can help A LOT.

You might start with labels on the outlets. There is a EIA/TIE 606 administration standard revision due out soon that is supposed to simplifiy and standardize this area that has always been a problem. But any system you come up with is better than nothing.

I sometimes keep a narrative log of changes. This is a plain English language description of what was done and why.(!)

After time passes and your memory fades, a few paper notes can be worth their weight in gold.

Yours,
Mike

 

[DanielBowen]

What I wanted to do, was write a batch file that executed on bootup to perform a trace that located the switch that the user was patched into. I am not interested in specific ports, just the Cat they uplink into.

Trouble is, I wouldnt want a users wks telnetting to a Catalyst

Thanks all for your help !