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New Member

CATOS- help with spanning tree please

Hi Everyone

I haave a problem with CATOS, something which ive never used and was wondering if you give me a hand. Basically I need to change the spanning tree from rapid-pvst+ to an open standard as i will be connecting some H3c switches. The problem is when i look at my spanning tree options in CATOS i only get:

pvst+                      Run Per VLAN Spanning Tree
  mistp                      Run Per Instance Spanning Tree
  mistp-pvst+                Run MISTP but allow remote PVST+/RAPID-PVST+
  mst                        Run IEEE MST (802.1s-based)
  rapid-pvst+                Run Per VLAN Rapid Spanning Tree (802.1w)

The H3c switch supports:

IEEE 802.1D (STP)

IEEE 802.1w (RSTP)

IEEE 802.1s (MSTP)

Now what i was wondering is. will RSTP 802.1w on the H3c switch work with rapid-pvst+ on the cisco switch? I thought rapid pvst+ was cisco properietary but next to the description it clearly states 802.1w. I want to use rapid spanning tree instead of mstp.

If i have no choice but to change the spanning tree to mstp on the cisco switch then ill need to make the changes without making the spanning tree go haywire. Basically I have 2 cores. Core 1 which is the root bridge and core 2 has spanning tree disabled for the relevent vlans. There are a few switches connecting to both cores in a loop. what the best practice when changing the spanning tree to mstp? Just a bit nervous as i dont want to bring everything down. (IOS would have been soo much easier).

I was thinking about first increasing the bridge priority on core 2 to something like 32768 and then changing it to mstp and then changing the the mstp on core 1 last. Would that work without a hitch?

Here is some of the config for both the cores:

core 1:

#stp mode
set spantree mode rapid-pvst

#vlan                         <VlanId>
set spantree priority 12     1
set spantree priority 8192   10
set spantree priority 8192   20
set spantree priority 8192   30
set spantree priority 8192   40
set spantree priority 8192   50

core 2:

#stp mode
set spantree mode rapid-pvst

set spantree disable  30
set spantree priority 8191   30
set spantree disable  40
set spantree priority 8191   40
set spantree disable  50
set spantree priority 8191   50
set spantree disable  60
set spantree priority 8191   60

I know  its a long one but I really appreciate your help with this one.


New Member

Re: CATOS- help with spanning tree please

Sorry guys, dont think ive explained myself too clearly above. My main issue is with the rapid-pvst+ which I beleive is cisco proprietary. Ide like to know why it states 802.1w in brackets in the description from catos? If it is 802.1w then it should talk to rstp 802.1w on the H3c switches right? Im just a bit confused with the rapid-pvst+ on the cisco switch as i thought 802.1w was an open standard.