H3C S7500E Series Ethernet Switches Operation Manual

Operation Manual – MSTP

H3C S7500E Series Ethernet Switches Chapter 1 MSTP Configuration

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II. Network diagram

GE2/0/1

Device A

Device B

Third-party

device

Root port

Designated port

Blocked port

GE2/0/1

GE2/0/2

Figure 1-6 Digest Snooping configuration

III. Configuration procedure

1) Enable Digest Snooping on Device A

# Enable Digest Snooping on GigabitEthernet2/0/1.

<DeviceA> system-view

[DeviceA] interface GigabitEthernet 2/0/1

[DeviceA-GigabitEthernet2/0/1] stp config-digest-snooping

# Enable global Digest Snooping.

[DeviceA-GigabitEthernet2/0/1] quit

[DeviceA] stp config-digest-snooping

2) Enable Digest Snooping on Device B (the same as above, omitted)

1.7 Configuring No Agreement Check

Two types of messages are used for rapid state transition on designated RSTP and

MSTP ports:

z Proposal: sent by designated ports to request rapid transition

z Agreement: 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 differences between RSTP and MSTP switches are:

z For MSTP, the downstream device’s root port sends an agreement packet only

after it receives an agreement packet from the upstream device.

z For RSTP, the down stream device sends an agreement packet regardless of

whether an agreement packet from the upstream device is received.