How to add 2960-X to an existing stack without downtime using (spanning-tree mode rapid-pvst)

[monasir]

Hi everyone,

We are trying to add 2 Cisco 2960-X 48 ports switch to an existing stack.

In the past a couple of times  we encounter a downtime of 30 seconds.

Is there a way to add switch members smoothly without downtime.

We are using " spanning-tree mode rapid-pvst" on all the configurations of the switches.

I'm trying to find a way to add these members without network outage of 30 seconds.

[Leo Laohoo]

I have never experienced having an much as a "glitch" when adding a switch to a stack.

IMPORTANT:  Make sure the new switches are loaded with the same firmware version as the existing stack. 

1.  Make sure the new switches are powered off before attaching the stacking cable

2.  Apply power only when all the stacking cables are connected.

[monasir]

Hi Leo,

I am familiar with the 2 steps you have mentioned, but what i need to know is how can i add those 2 member with rapid -pvst without having a network outage of 30 seconds.

[Leo Laohoo]

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@monasir wrote:

I am familiar with the 2 steps you have mentioned, but what i need to know is how can i add those 2 member with rapid -pvst without having a network outage of 30 seconds.

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It doesn't matter what flavour of spanning-tree is used.  It is not meant to affect anything.  

Adding one (or more) switches to an existing stack is not meant to have an impact to the operation of the entire stack.  

The only thing I can think of that can cause this to happen is the stack running a buggy code.  Otherwise, I've added a lot of switches in stacks and never have I seen any impact.  

[Deepak Kumar]

Hi,

The same function I did last week and there was no outage.

Note: make sure that the existing switch and new switches are on the same firmware version. If there are some changes in the firmware version then I advise using the "Software upgrade auto" feature. And make sure Switch number also added on old and new switches.

1. Make power of new switches.

2. Connect Stack cable properly. Don't connect a network cable yet.

3. Power on the switch and wait until switch join the stack. It will take approx 10 minutes

[Vishnu Vardhan S]

Connect the stack cables after powering on the switch then the network cable. Make sure the switch is in same version