NEC N8406-022 manual Common Internal Spanning Tree configuration, CIST bridge configuration

Common Internal Spanning Tree configuration

The Common Internal Spanning Tree (CIST) provides compatibility with different MSTP regions and with devices running different Spanning Tree instances. It is equivalent to Spanning Tree Group 0.

The following table describes the commands used to configure CIST commands.

Table 80 CIST Configuration commands

Command	Description
spanning-tree mstp	Adds VLANs to the CIST. Enter one VLAN per line, and press Enter to add the
cist-add-vlan <1-4095>	VLANs. Command mode: Global configuration
default spanning-tree	Resets all CIST parameters to their default values.
mstp cist	Command mode: Global configuration
show spanning-tree mstp	Displays the current CIST configuration.
cist	Command mode: All

CIST bridge configuration

CIST bridge parameters are used only when the switch is in MSTP mode. CIST parameters do not affect operation of STP/PVST.

The following table describes the commands used to configure CIST Bridge Configuration commands.

Table 81 CIST Bridge Configuration commands

Command	Description
spanning-tree mstp cist-	Configures the CIST bridge priority. The bridge priority parameter controls
bridge priority {<0-65535>}	which bridge on the network is the MSTP root bridge.
	To make this switch the root bridge, configure the bridge priority lower than
	all other switches and bridges on your network. The lower the value, the
	higher the bridge priority. The range is 0 to 65535, and the default is
	32768.
	This command does not apply to RSTP. See the "Bridge Spanning Tree
	configuration" section for more information.
	Command mode: Global configuration

spanning-tree mstp cist- bridge maximum-age {<6-40>}

Configures the CIST bridge maximum age. The maximum age parameter specifies the maximum time the bridge waits without receiving a configuration bridge protocol data unit before it reconfigures the MSTP network. The range is 6 to 40 seconds, and the default is 20 seconds. This command does not apply to RSTP. See the "Bridge Spanning Tree configuration" section for more information.

Command mode: Global configuration

spanning-tree mstp cist- bridge forward-delay {<4-

30>}

Configures the CIST bridge forward delay parameter. The forward delay parameter specifies the amount of time that a bridge port has to wait before it changes from the listening state to the learning state and from the learning state to the forwarding state. The range is 4 to 30 seconds, and the default is 15 seconds.

This command does not apply to RSTP. See the "Bridge Spanning Tree configuration" section for more information.

Command mode: Global configuration

show spanning-tree mstp cist Displays the current CIST bridge configuration. Command mode: All

Configuration Commands 76