Spanning-Tree Rootguard; Spanning-Tree Tcflush (Global Mode) - Planet SGS-6341 Series Command Manual

The bridge ID can be altered by changing the priority of the switch. Further, the priority information
can also be used for voting of the root bridge and the specified ports. The bridge priority value of the
switch is smaller, however the priority is higher.
Example:
Configure the priority is 4096.
Switch(config)#spanning-tree priority 4096

14.1.28 spanning-tree rootguard

Command:
spanning-tree rootguard
no spanning-tree rootguard
Function:
Set the port is root port, "no spanning-tree rootguard" command sets the port is non-root port.
Default:
Port is non-root port.
Command Mode:
Port Mode
Usage Guide:
The command is used in Port Mode, if the port is configured to be a rootguand port, it is forbidden to
be a MSTP root port. If superior BPDU packet is received from a rootguard port, MSTP did not
recalculate spanning-tree, and just set the status of the port to be root_inconsistent (blocked). If no
superior BPDU packet is received from a blocked rootguard port, the port status will restore to be
forwarding. The rootguard function can maintain a relative stable spanning-tree topology when a
new switch is added to the network.
Example:
Set the port 1 is root port.
Switch(Config-If-Ethernet1/0/1)#spanning-tree rootguard

14.1.29 spanning-tree tcflush (Global mode)

Command:
spanning-tree tcflush {enable| disable| protect}
no spanning-tree tcflush
Function:
Configure the spanning-tree flush mode once the topology changes. "no spanning-tree tcflush"
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