Spanning tree vlan root primary on B-series, C-series, K-series, N-series, S-series

[Francisco_Garc1]

Hi, maybe is a silly or complex question but ...

Recently we discovered an issue on our data center network where a vlan suffered connection loss; as we found it was all caused by an old switch that was automatically elected as root primary for the affected vlan. We proceded to configure our core chassis to be primary root at the mentioned vlan and problem was solved. the core switch is non enterasys/extreme and the old switch was a very old enterasys switch. probably the old switch dont had the ram/cpu/forwarding capacity to be a root on any vlan !!!

Now, the thing is that i want to make sure that all of my remote sites ( that are almost completely enterasys/extreme based ) had the appropiate settings in order to ensure that the most capable enterasys/extreme switch onsite is primary root and not had the issue of a slow switch performing as primary root.

how can it be done ? thanks in advance....

[Erik_Auerswald]

Hi Francisco,

yes, you should use a priority of 0 for the root switch, and priority 4096 for the secondary root switch.

Erik

[Francisco_Garc1]

thanks Erik. please let me ask you if by setting prioirities you mean to lower those for something like "0" ??? . so that's essentially what Glyn is stating on this same thread. You've been very helpful...

[Eric_Burke]

Not sure if there is a simple way to do this (other than dropping the priority on those you want as root bridge). The problem you found is pretty common. Since the MAC address is used to judge when they're set to default, it's often the oldest units that end up with the lowest MAC. Hopefully someone can provide a better method of setting them all simply...