R0106-HP MSR Router Series Layer 2 - LAN Switching Configuration Guide(V7)
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Enabling the spanning tree feature in STP/RSTP/MSTP mode
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enable the spanning tree
feature.
stp global enable
By default, the spanning tree
feature is disabled globally.
3. Enter Layer 2 Ethernet interface
view.
interface interface-type
interface-number
N/A
4. (Optional.) Enable the
spanning tree feature for the
port.
stp enable
By default, the spanning tree
feature is enabled on all ports.
Enabling the spanning tree feature in PVST mode
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enable the spanning tree
feature.
stp global enable
By default, the spanning tree
feature is disabled globally.
3. Enable the spanning tree
feature in VLANs.
stp vlan vlan-id-list enable
By default, the spanning tree
feature is enabled in VLANs.
4. Enter Layer 2 Ethernet interface
view.
interface interface-type
interface-number
N/A
5. Enable the spanning tree
feature on the port.
stp enable
By default, the spanning tree
feature is enabled on all ports.
Performing mCheck
The mCheck feature enables user intervention in the port status transition process.
When a port on an MSTP, RSTP, or PVST device connects to an STP device and receives STP BPDUs, the
port automatically transits to the STP mode. However, the port cannot automatically transit back to the
original mode when the following conditions exist:
• The peer STP device is shut down or removed.
• The port cannot detect the change.
To forcibly transit the port to operate in the original mode, you can perform an mCheck operation.
For example, Device A, Device B, and Device C are connected in sequence. Device A runs STP, Device
B does not run any spanning tree protocol, and Device C runs RSTP, PVST, or MSTP. In this case, when
Device C receives an STP BPDU transparently transmitted by Device B, the receiving port transits to the
STP mode. If you configure Device B to run RSTP, PVST, or MSTP with Device C, you must perform mCheck
operations on the ports interconnecting Device B and Device C.
Configuration restrictions and guidelines
The mCheck operation takes effect on devices operating in MSTP, PVST, or RSTP mode.