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Performing mCheck Operation 
Ports on an MSTP-enabled switch can operate in three modes: STP-compatible, RSTP-compatible, 
and MSTP. 
If a port on a device running MSTP (or RSTP) connects to a device running STP, this port will 
automatically migrate to the STP-compatible mode. However, it will not be able to migrate automatically 
back to the MSTP (or RSTP) mode, but will remain working in the STP-compatible mode under the 
following circumstances: 
z  The device running STP is shut down or removed. 
z  The device running STP migrates to the MSTP (or RSTP) mode. 
By then, you can perform an mCheck operation to force the port to migrate to the MSTP (or RSTP) 
mode. 
Configuration Prerequisites 
MSTP runs normally on the switch. 
Configuration Procedure 
You can perform the mCheck operation in the following two ways. 
Perform the mCheck operation in system view 
Follow these steps to perform the mCheck operation in system view: 
To do...  Use the command...  Remarks 
Enter system view 
system-view 
— 
Perform the mCheck operation 
stp [ interface interface-list ] 
mcheck 
Required 
 
Perform the mCheck operation in Ethernet port view 
Follow these steps to perform the mCheck operation in Ethernet port view: 
To do...  Use the command...  Remarks 
Enter system view 
system-view 
— 
Enter Ethernet port view 
interface interface-type 
interface-number 
— 
Perform the mCheck operation 
stp mcheck 
Required 
 
Configuration Example 
# Perform the mCheck operation on Ethernet 1/0/1.  
1)  Perform this configuration in system view 
<Sysname> system-view 
[Sysname] stp interface Ethernet 1/0/1 mcheck 
2)  Perform this configuration in Ethernet port view 
<Sysname> system-view