STP Config

[jeff.cook]

I'm looking to create a loop in my network. I want to control how STP breaks the loop. I want the root to be broken from the secondary. I have attached a drawing.

Switch 1 & 4 are in the data center and are the routers for the vlan. I would like to keep the traffic off the direct connection between the two if possible as it is a trunk for the servers.

Please let me know you ideas.

Thank You

[Jason Fraioli]

You could manually prune all vlans except the server vlan from those two interfaces.

[jeff.cook]

I could, but then if there was a link failure it would not fail-over.

[glen.grant]

this link might help . You will probably have to put a high port priority on the vlan on the link you want blocked. You set these per vlan .

https://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a00800ae96a.shtml

[Francois Tallet]

Just configure a *huge* cost on the port of switch 4 going to switch 1. That should do the trick.

Well, if you want to define *huge* in a more precise way, just sum up the cost of the "northbound" ports of the bridges on the alternate path on the right (port leading to sw1 on sw2, port leading to sw2 on sw3 and port leading to sw3 on sw4), and make sure the cost you configure on the port I mention above is higher.

Regards,

Francois