Spanning tree and link failure recovery

[zzz01]

Hi,

We have three switches in a ring topology for our "Optical Local Loop" project. Spanning tree 802.1D is implemented with a blocked (x) port. The switches type is "regular" 3750 series model WS-C3750G-12S-E (see my first thread:

http://www.tek-tips.com/viewthread.cfm?qid=1406679&page=1

).

Traditionally, it takes 30 seconds for 802.1D to recover from a link failure. The problem is that our marketing department wants a convergence in only 1 ms (oops!).
I tried "Resilient Ethernet Protocol". Unfortunately, it works only on Metro switches...

Now, from your experiences, what are the different options (with the least changes in switches) I have to get the closest possible to 1 ms as a recovery time?


Thx in advance.


Regards.

 

[vipergg]

Your best bet would be to implement Rapid Per vlan Spanning Tree , this will make the failover pretty quick though 1 ms is not possible , it will be like 2 -3 seconds with rapid spanning from our experiences, your switches will support rapid spanning tree .

 

[vipergg]

good link for configuring spanning tree and rapid spanning . Believe it is as simple as the command spanning-tree mode rapid-pvst " .

http://www.cisco.com/en/US/products...figuration_guide_chapter09186a00805a650a.html