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Role preemption mechanism
As shown in
, the link on Port1 of Device C is the master link, and the link on Port2 of Device
C is the slave link. Once the master link fails, Port1 is automatically blocked and placed in the standby
state, while Port2 takes over to forward traffic. If the smart link group is configured with role
preemption, Port1 takes over to forward traffic as soon as its link recovers, while Port2 is automatically
blocked and placed in the standby state.
Load sharing mechanism
A ring network may carry traffic of multiple VLANs. Smart Link can forward traffic of different VLANs in
different smart link groups, thus implementing load sharing.
To implement load sharing, you can assign a port to multiple smart link groups (each configured with
different protected VLANs), making sure that the state of the port is different in these smart link groups.
In this way, traffic of different VLANs can be forwarded along different paths.
You can configure protected VLANs for a smart link group by referencing MSTIs.
Smart Link Collaboration Mechanisms
Smart Link cannot sense by itself when faults occur on the uplink of the upstream devices, or when
faults are cleared. To monitor the uplink status of the upstream devices, you can configure the Monitor
Link function to monitor the uplink ports of the upstream devices. Monitor Link adapts the up/down
state of downlink ports to the up/down state of uplink ports, thus triggering Smart Link to perform link
switchover on the downstream device.
For more information about Monitor Link, see
Monitor Link Configuration
in the
High Availability
Configuration Guide
.
Smart Link Configuration Task List
Complete the following tasks to configure Smart Link:
Task
Remarks
Configuring Protected VLANs for a Smart Link Group
Required
Configuring Member Ports for a Smart Link Group
Required
Configuring Role Preemption for a Smart Link Group
Optional
Enabling the Sending of Flush Messages
Optional
Enabling the Receiving of Flush Messages
Required