Skip to main content
Start a Conversation

Unsolved

This post is more than 5 years old

FjordNestor

2 Posts

13465

September 5th, 2007 20:00

PowerConnect 6224 stacking issue

Hi,
 
I currently have 2 Dell PowerConnect 6224 with the Stacking Module configured. Everything is setup and working properly. Switch 1 is Master and Switch 2 is Member. On port g1 of each switch there's a connection to our ISP so we have a redundant link to the Internet. We confirm that Spanning Tree works as expected when the ISP stops each links we revert to the other one with a few packets lost.
 
Everything works good as well when we reset the Member Switch within the stack. However, when we reset the Master Switch or we force the Member Switch to become the Master switch, then we lose connectivity to the ISP for a little more than a minute (around 70-75 seconds). IMHO I would have thought that a stack would help us prevent this.
 
From the logs, it seems that there's a lot of things going on to synch both unit and Spanning Tree is also part of the logs. Spanning Tree is converging fast enough and settings are within 6-8 seconds which should be enough.
 
What do you think about that? Is this normal?
 
Thanks!

nlspears

52 Posts

September 7th, 2007 19:00

I think the time span is because the switches are swapping roles. When you reset the master switch, then the member switch has change to the master, one the former master switch powers up it notices that it can't be the master anymore and changes to a member switch.

FjordNestor

2 Posts

September 7th, 2007 19:00

Hi,
 
After calling Tech Support, I've been told that resync of the stack is by design. So when the stack renegotiates after a Master failure/reset, the slave switch then "resets" itself to become the master. This stops ALL communication between any hosts/devices connected to this switch (I mean every leds go out like it is being reset). The communication then comes back once the switch becomes the Master.
 
So if you think your stack is redundant, think again. If you Master fails, you'll lose connectivity for about a little more than a minute which is too long in a redundant environment.
 
As a comparison, Cisco Catalyst 3750 can be stacked and the communication is not lost when the master switch fails.
 
Sylvain

Was this post helpful?

View All

0 events found

No Events found!

Top