Cisco Systems 3750E Configuring the Maximum-Aging Time, Configuring the Maximum-Hop Count, 19-24

Chapter 19 Configuring MSTP

Configuring MSTP Features

Configuring the Maximum-Aging Time

Beginning in privileged EXEC mode, follow these steps to configure the maximum-aging time for all MST instances. This procedure is optional.

	Command	Purpose
Step 1
	configure terminal	Enter global configuration mode.
Step 2
	spanning-tree mst max-age seconds	Configure the maximum-aging time for all MST instances. The
		maximum-aging time is the number of seconds a switch waits
		without receiving spanning-tree configuration messages before
		attempting a reconfiguration.
		For seconds, the range is 6 to 40; the default is 20.
Step 3
	end	Return to privileged EXEC mode.
Step 4
	show spanning-tree mst	Verify your entries.
Step 5
	copy running-config startup-config	(Optional) Save your entries in the configuration file.

To return the switch to its default setting, use the no spanning-tree mst max-ageglobal configuration command.

Configuring the Maximum-Hop Count

Beginning in privileged EXEC mode, follow these steps to configure the maximum-hop count for all MST instances. This procedure is optional.

	Command	Purpose
Step 1
	configure terminal	Enter global configuration mode.
Step 2
	spanning-tree mst max-hops hop-count	Specify the number of hops in a region before the BPDU is
		discarded, and the information held for a port is aged.
		For hop-count, the range is 1 to 255; the default is 20.
Step 3
	end	Return to privileged EXEC mode.
Step 4
	show spanning-tree mst	Verify your entries.
Step 5
	copy running-config startup-config	(Optional) Save your entries in the configuration file.

To return the switch to its default setting, use the no spanning-tree mst max-hopsglobal configuration command.

Specifying the Link Type to Ensure Rapid Transitions

If you connect a port to another port through a point-to-point link and the local port becomes a designated port, the RSTP negotiates a rapid transition with the other port by using the proposal-agreement handshake to ensure a loop-free topology as described in the “Rapid Convergence” section on page 19-10.

	Catalyst 3750-E and 3560-E Switch Software Configuration Guide
19-24	OL-9775-02