H3C S7500X Series Configuration Manual page 261

Figure 16 Network diagram
MST region
GE1/0/1
Device A
Configuration procedure
# Enable Digest Snooping on GigabitEthernet 1/0/1 of Device A and enable global Digest Snooping
on Device A.
<DeviceA> system-view
[DeviceA] interface gigabitethernet 1/0/1
[DeviceA-GigabitEthernet1/0/1] stp config-digest-snooping
[DeviceA-GigabitEthernet1/0/1] quit
[DeviceA] stp global config-digest-snooping
# Enable Digest Snooping on GigabitEthernet 1/0/1 of Device B and enable global Digest Snooping
on Device B.
<DeviceB> system-view
[DeviceB] interface gigabitethernet 1/0/1
[DeviceB-GigabitEthernet1/0/1] stp config-digest-snooping
[DeviceB-GigabitEthernet1/0/1] quit
[DeviceB] stp global config-digest-snooping
Configuring No Agreement Check
In RSTP and MSTP, the following types of messages are used for rapid state transition on
designated ports:
•
Proposal—Sent by designated ports to request rapid transition
•
Agreement—Used to acknowledge rapid transition requests
Both RSTP and MSTP devices can perform rapid transition on a designated port only when the port
receives an agreement packet from the downstream device. RSTP and MSTP devices have the
following differences:
•
For MSTP, the root port of the downstream device sends an agreement packet only after it
receives an agreement packet from the upstream device.
•
For RSTP, the downstream device sends an agreement packet whether or not an agreement
packet from the upstream device is received.
Device C
Root bridge
GE1/0/1 GE1/0/2
GE1/0/2 GE1/0/2
Device B
Root port
Designated port
Blocked port
Normal link
GE1/0/1
Blocked link
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