H3C S6850 Series, Configuration Manual

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interface interface-type interface-number
4.
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
1.
Enter system view.
system-view
2.
Enable the spanning tree feature.
stp global enable
When the device starts up with initial settings, the spanning tree feature is globally disabled by
default.
When the device starts up with factory defaults, the spanning tree feature is globally enabled by
default.
For more information about the initial settings and factory defaults, see
Fundamentals
Configuration Guide
.
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 interface view.
interface interface-type interface-number
5.
Enable the spanning tree feature on the port.
stp enable
By default, the spanning tree feature is enabled on all ports.
Performing mCheck
About mCheck
The mCheck feature enables user intervention in the port state 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.
Restrictions and guidelines
The mCheck operation takes effect on devices operating in MSTP, PVST, or RSTP mode.