Overview of MSTP
MSTP is a multiple spanning tree protocol that allows multiple spanning trees to run in a switching environment. Each spanning tree is called an instance. MSTP trims the routing loop network into an acyclic tree network , To avoid the occurrence of broadcast storms, while also providing multiple redundant paths for data forwarding, to achieve VLAN data load balancing in the data forwarding process, MSTP is also compatible with STP and RSTP.
Basic principles of MSTP
(1) MSTP network hierarchy
A two-layer switching network can be divided into multiple MST regions, each spanning tree region can be divided into multiple MSTIs, and each instance can map multiple A VLAN
(2) MST domain
The MST domain is a multiple spanning tree domain. The network segments between multiple switches in the local area network constitute a local area network. There can be multiple MST domains. Physically directly or indirectly connected
(3) MSTI
Multiple MSTIs can run in one MSTI domain. MSTIs are independent of each other. MSTI can correspond to one or more VLANs, but one VLAN can only correspond to one MSTI .
(4) Port role
The roles in MSTP mainly include root port, designated port, reserve port, backup port and edge port. All port roles except edge ports participate in the MSTP calculation process.
(5) MSTP port status
There are three main types:
Forwarding: Forwarding status
Learning: Learning status
Discarding: Blocking status
The following introduces experimental cases
The gateways of the two clients are the IPs of the two ports of the router
1. Configure the IP address of the client and router. R1 is configured as follows
2. Configure VLAN and Trunk
SW1 configuration is as follows:
S2 configuration is as follows:
S3 configuration is as follows:
3. Configure MSTP
【S1】stp mode mstp // Configure the switch to MSTP mode
【S1】stp region-configuration // Enter MSTP Configuration mode
[S1-mst-region] region-name asd // Configure the domain name as asd
[S1-mst-region] revision-level 1 // Configure the version level to 1
[S1-mst -region] instance 1 vlan 10 // add vlan10 to instance 1
[S1-mst-region] instance 2 vlan 20 // add vlan20 to instance 2
[S1-mst-region] active region- configuration // Activate the configuration
[S1-mst-region]quit
[S1]stp instance 1 root perimary //Configure this switch as the primary root of instance 1
[S2]stp instance 2 root secondary // Configure this switch as the standby root of instance 2
S2 configuration is as follows
R3 configuration is as follows:
4 .Verify
Use the display stp brief command on S3 to view the role and status information of the STP interface
You can also use pc1 to access pc2
