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I have two Cisco Catalyst 2960-X Series switches which I've stacked. I want the master to be switch 1 and the member to be switch 2.

After doing research on stacking the switches, it's my understanding that the election takes place with the highest priority switch becoming the master during the election process.

Once I set this, the stack was restarted and the member switch that I want keeps getting elected as the master.

Switch#  Role   Mac Address     Priority Version  State
----------------------------------------------------------
 1       Member 40a6.e8ba.ac80     15     4       Ready
*2       Master bcc4.9385.c980     14     4       Ready

As you can see, the switch with the lowest priorty is still being elected as the master, and I don't quite understand why, unless I'm misunderstanding this election concept?

If I turn on the switch I want as master first, and then turn on the member switch I can make it a master this way. However, if I ever need to restart the stack then bcc4.9385.c980 always elects itself as the master.

So to clarify what I'm after, I would like the below:

Switch#  Role   Mac Address     Priority Version  State
----------------------------------------------------------
*1       Master 40a6.e8ba.ac80     15     4       Ready
 2       Member bcc4.9385.c980     14     4       Ready

Please advise how I can acheive this.

Thanks.

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3 Answers 3

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According to Cisco guide, the switch with higher priority value should become the stack master, but looks like it does not work in this case.

You can try (check if it works after each step, make sure you save the configuration before reloading the stack):

  • Change priority of Switch#2 to 1
  • Change priority of Switch#1 and #2 to the same value, thus the Switch#1 with lower MAC address should become master.

  • Make sure they have same hardware model and IOS image version. If not, upgrade their IOS.

  • If it is still not working, break the stack into two seperate ones, unprovision, renumber each of them. If possible, try to clear their configuratoin. Then stack them back again.

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  • 1
    Thanks for this. I've also realised from documentation that the stack elects the switch which contains the config as the master. Interesting to note about the lowest MAC address too.
    – BabyPython
    Oct 5, 2017 at 12:23
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Try setting the priority of the desired member switches to something even lower, like 10 or less... Should do the trick. Leave the desired Master at 15.

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  • Ok I've set the other switch to a priority of 5 and left the desired master switch as 15. Saved the config and reloading the stack as we speak. Is there a reason you know of why there needs to be a significant gap in priority values here when it comes to stacking?
    – BabyPython
    Oct 4, 2017 at 15:12
  • Unfortunately, I'm simply relaying my own experience with the subject. Hopefully someone with that answer will see this and comment to educate us both on the root of the cause.
    – Confusias
    Oct 4, 2017 at 15:16
  • That hasn't worked. Perhaps it's the way the stacking cables are connected that's causing the issue. It's the only thing I can think of at this stage.
    – BabyPython
    Oct 4, 2017 at 15:20
  • I don't see any reference to cabling playing a factor. Here's the reference URL I used. goo.gl/ECNJsn
    – Confusias
    Oct 4, 2017 at 15:53
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your understanding is correct, election takes place with the highest priority switch becoming the master during the election process.

If you restart the whole stack,switch 1 will become the master.

IF you power down the switch 1 & power on the switch 2, election will take place only one participant switch 2 with 14 priority makes the master switch.

5 min later switch 1 will booting means already master is elected even though if switch 1 has the highest priority 15 switch 1 will be the member.

while the time of election all the switch should alive then only highest

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  • If I restart the whole stack when sw1 is the master (pri 15) and sw2 is the member (pri 14), then sw2 becomes the master and sw1 becomes the member which is what I don't want. So I really don't understand how this is happening. The only way I can make sw1 the master is if I boot it up first
    – BabyPython
    Oct 5, 2017 at 9:25

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