stupid stack question

[Hubsi-Smith]

Hello,
I have an understanding problem with stacked switches. For example, I have stacked 4 3750 switches. How do I figure out, on physical side, which one has interface X/Y/Z?

[balaji.bandi]

here is stacking information with detailed steps : ( Master switch or switch 1 start from interface 1/0/1 -Switch 2 2/0/1- Switch 3 3/0/1 -switch 4 4/0/1 so on)

show switch give information ( we also suggest always label the devices Physical to identify)

https://www.cisco.com/c/en/us/support/docs/switches/catalyst-3750-series-switches/71925-cat3750-create-switch-stks.html

[Reza Sharifi]

Hi,

How do I figure out, on physical side, which one has interface X/Y/Z?

On the physical side, you would need to mark each switch in the rack or cabinet. For example, in a 4 stack switch environment, the first switch in the rack at the top can be sw-1 and the last switch at the bottom would be switch 4.

Example:

rack-1 RR20 switch-1

rack-1 RR21 switch-2

rack-1 RR23 switch-3

rack-1 RR24 switch-4

So, now as an example, when you configure port 2/0/20 logically from the master switch, that is switch 2 port 20.

HTH

[Leo Laohoo]

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@Hubsi-Smith wrote:

How do I figure out, on physical side, which one has interface X/Y/Z?

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Are you trying to figure out, physically, which of the switches is "stack X"?

[paul driver]

Hello

sh switch stack-ports

[Seb Rupik]

Hi there,

Press the mode button until the STACK LED is lit. Look at the first few switchport LEDs. You should have 1 to 4 go green. On any switch, the flashing green switchport LED denotes its stack number.

This will give you your X value in X/Y/Z . As for the rest, Y is the module and Z is the port.

cheers,

Seb.

[Javier Acuña]

Thank you for reaching out to the Cisco community.
To validate the Stack use the following command sh switch * sh switch * this command will tell you which is the active and the standby with its respective mac add to know the ports sop use the command sh inter status it will show you a list where the following will be indicated:
Gi1 / 0/1 the first 1 represents the Swicth and the last 1 would be the port number within the first Swicth
In the case of an interface identified with G2 / 0/23 it would indicate that it is Sw 2 port 23,
For this example I used a G interface as a reference but you can have both G and Fast ethernet on the stack.

Remember to mark this Answer as a solution since this motivates you to be contributing in the community

[Joseph W. Doherty]

Laugh - good question.

Perhaps the easiest way, is when the switch stack was setup, someone labeled stack members with a stack number and/or your "standards" define how stacks are numbered from top to bottom or left to right.

If you don't have that, then perhaps something you can do, assuming stack is live, with a management connection, showing ports status, you might be able to identify stack member numbers that way.  E.g. member 1's ports 1, 3 and 4 are active, while member 2's ports 2 and 4 are active.

Or, connect a laptop (next to the stack), to an inactive port while connected to stack management and "watch" the port come up.  That will identify a stack member.  Of course, for the latter, you only need to do it for all stack members, less one, as the last switch will be identified by process of elimination.

Another, if some (or all) stack members or different models, that might identify individual stack members.  (For like models, again, connecting to all but one of them, will identify them.)

Forgoing assumes you can use show commands to identify logically how the stack members are numbered (the first number in the port).

For stack members having no copper ports, possibly you can use a small switch, with fiber connection, again to make connections.