H3C S7500E Series Ethernet Switches Operation Manual

Operation Manual – MSTP
H3C S7500E Series Ethernet Switches Chapter 1 MSTP Configuration
1-41
To do... Use the command... Remarks
Enable global digest
snooping
stp
config-digest-snooping
Required
Not enabled by default
Caution:
z You can only enable the Digest Snooping feature on the device connected to
another vendor’s device that uses a private key to calculate the configuration digest.
z With the Digest Snooping feature enabled, comparison of configuration digest is not
needed for in-the-same-region check, so the VLAN-to-instance mappings must be
the same on associated ports.
z With global Digest Snooping enabled, modification of VLAN-to-instance mappings
and removing of the current region configuration using the undo stp
region-configuration command are not allowed. You can only modify the region
name and revision level.
z You need to enable this feature both globally and on associated ports to make it
take effect. It is recommended to enable the feature on all associated ports first and
then globally, making all configured ports take effect, and disable the feature
globally to disable it on all associated ports.
z It is not recommended to enable Digest Snooping on the MST region edge port to
avoid loops.
z It is recommended to enable Digest Snooping first and then MSTP. Do not enable
Digest Snooping when the network works well to avoid traffic interruption.
1.6.3 Configuration Example
I. Network requirements
z Device A and Device B connect to a third-party’s router and all the routers are in
the same region.
z Enable Digest Snooping on Device A and Device B so that the three routers can
communicate with one another.