Extreme Stack Dual Master Errors – Resolved

Before I start outlining the Extreme Stack Dual Master Errors I’ve had recently let me tell you what I’ve been up to . It has been a while since my last post and I’ve decided to embark on my CCIE. I’ve been busy preparing a lab for the CCIE in Routing and Switching. I’ll be providing updates and links to CCIE resources and tips I come across while I study and learn.

On to the main point of this post – Extreme Stack Dual Master Errors

Extreme Stack Dual Master Errors

My client has an Extreme switch stack that started misbehaving after being in production for about 80 days. This particular stack consists of  5 switches and has so far been our unluckiest stack with a switch fault a couple of days after the initial install. I’ve been working with Extreme for a few years now and the first time I’ve had any major problems, have just been with this particular stack.

The stack has 2 x460-48p’s, 2 x460-24p’s and an x440. The first indication that something was wrong was the loss of all link lights in one of the 460-24’s. We patched the users into the switches directly above and below this switch and looked into the issue.

The following Extreme Stack Dual Master Errors were found in the log :

Slot-1: Slot-3 FAILED (1) Dual Master
Slot-1: Slot-3 has failed for the reason of "Dual Master"

After a switch reboot this was still causing issues and the decision was made to reboot the entire stack. This got everything back up and running.

After further research and reading through the release notes for the latest ExtremeXOS it seems that this is a known bug in software versions prior to 15.1.3, we were on

We’ve since upgraded the entire stack to 15.1.3 and have had no further Extreme Stack Dual Master Errors. The remaining stacks at the site will be upgraded progressively over the coming weeks. I’ll let you know if I come across any further issues.

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