RPVST+ / MST

[rherve]

Hello,

Actualy I have a customer to use a lot of vlan in his network (140).

Let me explaine the problem:

On 2960 catalyst switches, it can have a maximum of 255 vlan in the vlan database (OK) but only 128 spanning-tree instance (NOK)

When i use more than 128 vlans, the vlans pass to (no spanning-tree vlan xxx) in the configuration.

When I use MST is there the same limitation ? If someone has the response

THanks per advance

Hervé

[Reza Sharifi · Accepted solution]

Hi,

You can use MSTP to group you vlans together.

If the number of VLANs on the switch exceeds the  number of supported spanning-tree instances, we recommend that you  configure the IEEE 802.1s Multiple STP (MSTP) on your switch to map  multiple VLANs to a single spanning-tree instance. For more information  about MSTP, see

"Configuring MSTP."

Here is the config gude:

http://www.cisco.com/en/US/docs/switches/lan/catalyst2960/software/release/12.2_25_fx/configuration/guide/swvlan.html

HTH