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region to become the CST.
The MSTI is only valid within its MST region. An MSTI has nothing to do with MSTIs in
other MST regions. The bridges in a MST region receive the MST BPDU of other regions
through Boundary Ports. They only process CIST related information and abandon MSTI
information.
The MSTP bridge assigns a port role to each port which runs MSTP.
CIST port roles: root port, designated port, alternate port and backup port
On top of those roles, each MSTI port has one new role: master port.
The port roles in the CIST (root port, designated port, alternate port and backup port)
are defined in the same ways as those in the RSTP.
In a MSTP region, VLANs can by mapped to various instances. That can form various
topologies. Each instance is independent from the others and each distance can has its
own attributes such as bridge priority and port cost etc. Consequently, the VLANs in
different instances have their own paths. The traffic of the VLANs are load-balanced.
6.2 Configuring MSTP 6.2.1 MSTP Configuration Task Sequence 1. Enable the MSTP and set the running mode
2. Configure instance parameters
3. Configure MSTP region parameters
4. Configure MSTP time parameters
5. Configure the fast migrate feature for MSTP
1. Enable MSTP and set the running mode
Command Explanation
Global Mode and Interface Mode