rapid-pvst and Uplinkfast (cam-table flushing)

[rutte022]

If have configured rapid-pvst on a Cisco 3750 Switch, but i have also configured the uplinkfast feature, my question is what timer rules in case of flushing the cam table by a TP change ? The RSTP or the Uplinkfast feature

[milan.kulik]

Hi, I think UplinkFast should have no effect when running RPVST+.

"Rapid PVST+—This spanning-tree mode is the same as PVST+ except that is uses a rapid convergence based on the IEEE 802.1w standard. To provide rapid convergence, the rapid PVST+ immediately deletes dynamically learned MAC address entries on a per-port basis upon receiving a topology change. By contrast, PVST+ uses a short aging time for dynamically learned MAC address entries."

See http://www.cisco.com/univercd/cc/td/doc/product/lan/cat3750/12218se/3750scg/swstp.htm#1166029

"UplinkFast does not need to be configured further, as the mechanism is natively included and automatically enabled in RSTP."

See http://www.cisco.com/en/US/customer/tech/tk389/tk621/technologies_white_paper09186a0080094cfa.shtml#uplinkfast

or http://www.cisco.com/warp/public/473/146.pdf for .pdf version.

STP support pages:

http://www.cisco.com/cgi-bin/Support/browse/psp_view.pl?p=Technologies:Spanning_Tree&viewall=true

Regards,

Milan