Manage multiple switches

[Frank Sinatra]

In short: Is there a better way to find which port switch port a PC is connected to if you have multiple switches?

Longer version:

I am currently working in a building that has unconventional network design. There are four floors but all the patch panels are terminated on one floor and all the switches are there also. Patch panels are also mixed so one patch panel has cables coming from different floors. There are six patch panels (24-port) and three 3750 48-port switches

I have been working on cleaning up the cables but there's another problem. If I want to change the VLAN of a PC at, say, the third floor, I will have to go to each switch and look for its MAC Address. Is there a better way to do this? I can't do stack because the switches are old and the stack ports look damaged.

[Seb Rupik]

Hi there,

You could write an ansible playbook with two tasks. The first would run sh mac-add | inc <mac_address> and register it to a variable. The second task would output a string comprised of the switch name followed by the mac-address table entry, but it would only do this if the variable created in the first step wasn't empty, ie it had actually found the mac address.

Another option is a tool called NAV, which has a MAC search/ lookup function.

https://nav.uninett.no/

Personally I'd take the ansible route as it is a more versatile tool.

cheers,

Seb.

[Giovanni Alexander Molina]

Try using # traceroute mac 0001.0000.0204 0001.0000.0304 detail

The first one is the source and the second one is the destination.

Here an example:

Core#ping 10.242.3.18

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.242.3.18, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms

Core#show arp | include 10.242.3.18
Internet  10.242.3.18             9   0001.6c4d.c0f7  ARPA   Vlan3

Please find the example which you have requested.
==================================================

Core#traceroute mac 0001.6c4d.c0f7 0001.6c4d.c0f7 vlan 3
Source 0001.6c4d.c0f7 found on Accessswitch

Accessswitch(10.242.0.6) : Fa3/58 => Fa3/58
Destination 0001.6c4d.c0f7 found on Accessswitch

Layer 2 trace completed