02-07-2008 12:21 PM - edited 03-05-2019 09:01 PM
Dear NetPro!
what is the Difference between :
PVST
PVST+
R-PVST
MST
IN Wich cases we would use EACH One of theme?
many 10xs
02-07-2008 12:33 PM
Ali
PVST = Per vlan spanning tree. Each vlan has it own instance of spanning-tree. PVST is for use with ISL links.
PVST+ = same as above but it is for use with 802.1q
R-PVST = Rapid Spanning tree. A lot of the Cisco proprietary features in the original STP like uplinkfast/backbonefast/portfast were incorporated into R-PVST. R-PVST brings convergence times from approx 45 seconds to less than 5.
MST = Allows you to group a set of vlans into a single instance of spanning-tree. MST uses Rapid PVST so it also has rapid convergence times.
That is a very high overview. There are good links on Cisco's sites that cover each in more detail.
I have never used MST but as for the others i would recommend R-PVST if all your switches support it, then PVST+.
HTH
Jon
02-07-2008 12:39 PM
HI Jon
i have a 3550 Switch with PVST Mode and I COULD Ran spanning-tree portfast and Spanning-tree Uplink fast?how come this:
R-PVST = Rapid Spanning tree. A lot of the Cisco proprietary features in the original STP like uplinkfast/backbonefast/portfast were incorporated into R-PVST..
What about the Covergence of normal Pvst ?
10xs
02-07-2008 12:45 PM
Hi Ali
The features of uplinkfast/backbonefast/portfast were added by Cisco to try and improve the speed of convergence.
STP, PVST, PVST+ all have the same covergence time, as i say approx 45 seconds. There is little you can do to speed this up.
If you can run R-PVST+ and you have redundant links in your infrastructure then there is no good reason why you shouldn't. Be aware though that any switch that a vlan exists on needs to run R-PVST+ or for that vlan you will default back to normal PVST+ convergence times.
Jon
02-09-2008 10:45 PM
Hi,
I've noticed some odd behavior when using pvst+ and rapid-pvst+ with HP Procurve switches. Specifically, spanning-tree would work correctly when using access ports, but not when using 802.1q trunks. Yes, I know it's supposed to work, but I have not observed that.
MST was the only version that worked well with our HP switches.
-Kevin
Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: