19-105
Usage Guide:
The
MSTP uses max-age to count BPDU lifetime. In addition, MSTP also uses max-hop to count BPDU lifetime. The
max-hop is degressive in the network. The BPDU has the max value when it initiates from MSTI root bridge. Once
the BPDU is received, the value of the max-hop is reduced by 1. When a port receives the BPDU with max-hop as 0,
it drops this BPDU and sets itself as designated port to send the BPDU.
Example:
Set max hop to 32.
Switch(config)#spanning-tree max-hop 32
19.1.17 spanning-tree mcheck
Command:
spanning-tree mcheck
Function:
Force the port to run in the MSTP mode.
Command mode:
Port Mode
Default:
The port is in the MSTP mode by default.
Usage Guide:
If a network which is attached to the current port is running IEEE 802.1D STP, the port converts itself to run in STP
mode. The command is used to force the port to run in the MSTP mode. But once the port receives STP messages, it
changes to work in the STP mode again.
This command can only be used when the switch is running in IEEE802.1s MSTP mode. If the switch is running in
IEEE802.1D STP mode, this command is invalid.
Example:
Force the port 1/2 to run in the MSTP mode.
Switch(Config-If-Ethernet1/2)#spanning-tree mcheck