[c-nsp] mst & pvst

[Adam Greene]

Thanks, Mat, this helps!

----- Original Message ----- 
From: "Mateusz Blaszczyk" <blahu77 at gmail.com>
To: "Adam Greene" <maillist at webjogger.net>
Cc: <cisco-nsp at puck.nether.net>
Sent: Tuesday, March 25, 2008 4:04 PM
Subject: Re: [c-nsp] mst & pvst


> On 25/03/2008, Adam Greene <maillist at webjogger.net> wrote:
>> Hi,
>>
>>  I'm needing to set up a redundant trunk link between a 6509 and a 3750. 
>> The
>>  6509 is running MST, the 3750 PVST. Am I going to have issues? I am 
>> assuming
>>  so ...
>>
>>  Thanks,
>>  Adam
>>
>>
>>  ===
>>  6509
>>  ===
>>
>>  #MST (IEEE 802.1s)
>>  set spantree fwddelay 15 mst
>>  set spantree hello 2  mst
>>  set spantree maxage 20 mst
>>  set spantree mst maxhops 20
>>  set spantree priority 0     mst 0-15
>>  set spantree priority 32768 mst 16-4094
>>
>>  #MST Configuration
>>  set spantree mst config rollback force
>>  set spantree mst config name  revision 0
>>  set spantree mst 0 vlan 1-4094
>>  set spantree mst config commit
>>
>>  #vlan(defaults)
>>  set spantree enable  1-16,30,40,99-100,123,128,192,840,888
>>  set spantree fwddelay 15     1-16,30,40,99-100,123,128,192,840,888
>>  set spantree hello    2      1-16,30,40,99-100,123,128,192,840,888
>>  set spantree maxage   20     1-16,30,40,99-100,123,128,192,840,888
>>  set spantree priority 32768  2-16,30,40,99-100,123,128,192,840,888
>>
>>  ====
>>  3750
>>  ====
>>
>>  spanning-tree mode rapid-pvst
>>
>>
>
> read here
>
> http://www.cisco.com/en/US/products/hw/switches/ps708/products_configuration_example09186a00807b075f.shtml#mst1
> http://www.cisco.com/warp/public/473/147.html#invalid_configuration
>
> in a nutshell as long as mst priority for instance 0 (CST)  is better
> then PVST, you are good to go, but also keep in mind not to disable
> PVST on any VLANs on trunks between switches (no spt-disabled point to
> point vlans). Also don't do asymetric vlan configurations on trunks -
> remember that mst does not care about what vlans are actually
> provisioned on links but how are the instances configured.
>
> The links should give you a good starting point
>
> Best Regards,
>
> -mat
>
>
>
>
>