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tjwoollardFlag for United Kingdom of Great Britain and Northern Ireland asked on

Cisco switch issue

I have a stack of cisco 3750 switches connected using the stack-wise cables. Hence switch 1 is connected to 2, 2 to 3, 3 to 4 etc. switch 6 is connected back to 1.
 So there is a path to all switches if any switch fails.

here is a show stack output :

 1       Member bc16.650e.3a80     1      3       Ready
 2       Member e4d3.f11e.0300     2      3       Ready
 3       Member 6073.5c30.eb00     5      3       Ready
*4       Master 0006.f6bb.8500     15     3       Ready
 5       Member 6073.5c32.1300     4      3       Ready
 6       Member 4c4e.353a.bb00     3      3       Ready

When I removed the power from switch 1 switches 1 2 and 3 went down 4,5, and 6 stayed up. the sh switch said they were 'removed'.

 1       Member bc16.650e.3a80     1      3       removed
 2       Member e4d3.f11e.0300     2      3       removed
 3       Member 6073.5c30.eb00     5      3       removed
*4       Master 0006.f6bb.8500     15     3       Ready
 5       Member 6073.5c32.1300     4      3       Ready
 6       Member 4c4e.353a.bb00     3      3       Ready

 They came back when I powered on switch 1. I a, confused about this. I have read the cisco stuff on it but I can not get a definative answer regarding if this is normal or not.
Networking Hardware-OtherSwitches / Hubs

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Last Comment
tjwoollard

8/22/2022 - Mon
ryan80

No, this is not normal. The other switches should stay in the stack.
Jordan Medlen

I would check the stack cables between 3 and 4. Those stack cables for the 3750s are something awful, and I have had to reseat some in the past. It's possible that when you unplugged 1, that was providing the path to to 2 and 3 as far as the rest of the stack is concerned.

Check the logs on switch 3 and switch 4 to see if there are any entries regarding the stack at that point. Other than what I have mentioned, there could be something more seriously wrong.
Craig Beck

Are these 3750X switches using StackPower?
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William Peck
ASKER
tjwoollard

no they are no using stack power. each switch is supplied with 2 power supplies.
ASKER CERTIFIED SOLUTION
Craig Beck

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ASKER
tjwoollard

here it is but i can see the issue

hstack1#sh switch ne
  Switch #    Port 1       Port 2
  --------    ------       ------
      1         2             6
      2         3             1
      3        None           2
      4         5            None
      5         6             4
      6         1             5

1           Ok           Ok
    2           Ok           Ok
    3          Down          Ok
    4           Ok          Down
    5           Ok           Ok
    6           Ok           Ok
Jordan Medlen

As I stated, looks to be an issue with your stack cable between member switches 3 and 4. Try swapping or reseating the cable.
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Craig Beck

So there's your answer...

Switch 3 doesn't link to switch 4.  Therefore you have a break in your stack.  The only way to get to switch 3 from the master is via switch 1.

If you connect a stack cable between switch 3 and switch 4 you can remove the power from switch 1 and switches 2 and 3 will stay up in the stack.
ASKER
tjwoollard

OK