Configuring No Agreement Check - 3Com 4210G Series Configuration Manual

Digest Snooping configuration example
1) Network requirements
Device A and Device B connect to Device C, a third-party device, and all these devices are in the
same region.
Enable Digest Snooping on Device A and Device B so that the three devices can communicate
with one another.
Figure 4-6 Digest Snooping configuration
2) 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 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 config-digest-snooping

Configuring No Agreement Check

In RSTP and MSTP, two 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. The differences between RSTP and
MSTP devices are:
For MSTP, the downstream device's root port sends an agreement packet only after it receives an
agreement packet from the upstream device.
For RSTP, the down stream device sends an agreement packet regardless of whether an
agreement packet from the upstream device is received.
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