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Aruba CX how to exchange a defective VSF stack member

Hello Guys,

Last week I had to replace a defective switch in a VSF stack for the first time.
Those who know the IRF stack from HPE Comware know that this is feasible, but you have to configure a lot until the stack is up and running again after replacing a stack member.
With Aruba CX, the whole thing is totally simple in comparison.

Check the firmware version
First you must check the firmware version of the current VSF stack. According to the Aruba instructions, you do not have to do this because the VSF master automatically distributes the firmware to the members, but it did not work for me.
Now install the same firmware version on the new switch that the VSF stack uses.

VSF configuration on the new switch
In my case, the first member had failed. That’s why I didn’t have to do a renumber-to. All in all, only the following must be configured on the new switch:

For example, if the defective switch was member 2, you must perform a renumber:

conf t
vsf renumber-to 2
write mem
boot system primary

As soon as the new switch is up again, simply copy the VSF configuration from the master and put it on the new member.

In my case, the VSF stack consisted of 2 Aruba CX 6300 switches:

conf t
vsf split-detect mgmt
vsf secondary-member 2
vsf member 1
    type jl663a
    link 1 1/1/52
vsf member 2
    type jl663a
    link 1 2/1/52
write mem

Restoring the stack
Now, if you have not already done so, remove the defective switch and mount the new switch. Next, plug only the management port as split detection and the VSF link between the new switch and the rest of the VSF stack. Do not plug in the rest of the cables yet, because your ports are still all configured for VLAN 1 access. And your link aggregations are not configured yet either.
After about one to two minutes, the new switch automatically joins the VSF stack. The switch reboots and receives the complete port configuration of the old defective VSF member from the VSF master.
Now plug in the rest of the cables. that’s it.

Isn’t that cool? :D


Have a nice day!



4 Responses

  1. Hey,
    thanks for the great summary!
    But how about, when your failed switch is the master?
    Our Master is calling that an failure is imminent and I want to replace it.

    Do I have to promote an other switch to the new master, before being able to replace the master?
    Or is it enough to configure the vsf configuration, and the new switch gets the config from the secondary member?

    1. Hello Pascal,

      this is not a problem. It is the same as with member 2 or 3. I recommend that you make a backup of the configuration before replacing the vsf member. Just in case something does go wrong. I once linked you a document from Aruba. On page 19 it describes this. I would also announce a maintenance window of 60 minutes. With all the cable reconnection, disconnection and installation of the switch, it can take a while.

      1. Hey Phillip,

        thanks for the quick reply.
        It was as easy as you told.
        Simply gave him the vsf configuration and he got part of the stack as hoped.
        In my case I only needed 25 minutes, but this depends on the difficulty to do the cabling in the rack. In this case it were pretty easy.

        Thanks again! =)

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