Rapid Transition Configuration; Introduction - H3C S7500 Series Operation Manual

Operation Manual – MSTP
H3C S7500 Series Ethernet Switches
To do ...
Return to system
view
Enable the digest
snooping function
globally
Verify the
configuration
above
Note:
The digest snooping function is needed only when your S7500 switch is connected
to other vendors' proprietary spanning tree protocol-adopted switches.
To enable the digest snooping function successfully, you must first enable it on all
the ports of your S7500 switch that are connected to other vendors' proprietary
spanning tree protocol-adopted switches and then enable it globally.
To enable the digest snooping function, the interconnected switches must be
configured with exactly the same MST region-related configurations (including
region name, revision level, and VLAN-to-MSTI mapping).
The digest snooping function must be enabled on all the ports of your S7500 switch
that are connected to other vendors' proprietary spanning tree protocol-adopted
switches in the same MST region.
With the digest snooping function enabled, the VLAN-to-MSTI mapping cannot be
modified.
The digest snooping function is not applicable to edge ports of an MST region.

1.7 Rapid Transition Configuration

1.7.1 Introduction

Designated ports on switches adopting RSTP or MSTP use the following two types of
packets to implement rapid transition:
Proposal packets: Packets sent by designated ports to request rapid transition
Agreement packets: Packets used to acknowledge rapid transition requests
Both RSTP and MSTP switches can perform rapid transition operation on a designated
port only when the port receives an agreement packet from the downstream switch.
The difference between RSTP and MSTP switches are:
Use the command ...
quit
stp
config-digest-snooping
display
current-configuration
1-36
Chapter 1 MSTP Configuration
Remarks
—
Required
The digest snooping function
is disabled globally by default.
You can execute this
command in any view.