Chapter 5: Spanning Tree Protocol (STP) and Redundant Links

Commands:

5.2.9 Enabling and verifying Spanning Tree

IOS

Switch(config)#spantree vlan-list

Switch(config)#no spantree vlan-list

Switch#show spanning-tree [vlan]

Switch#show spanning-tree mod/num

CLI

Switch> (enable) set spantree enable [all | mod/num]

Switch> (enable) set spantree disable [all | mod/num]

Switch> (enable) show spantree [vlan]

Switch> (enable) show spantree mod/num

 

5.4.1 Establishing a root bridge

IOS

Switch(config)#spanning-tree portfast

Switch(config)#spanning-tree [vlan vlan-list] priority prty

CLI

Switch> (enable) set spantree portfast [mod/num] [enable|disable]

Switch> (enable) set spantree root [secondary] [vlan-list] [dia diameter] [hello hellotime]

 

 

5.4.3 Configuring the root cost

IOS

Switch(config-if)#spanning-tree [vlan vlan-list] cost cost

CLI

Switch> (enable) set spantree portcost mod/num cost

Switch> (enable) set spantree portvlancost mod/num [cost cost] [vlan-list]

 

 

5.4.4 Modifying port priority

IOS

Switch(config-if)#spanning-tree [vlan vlan-list] port-priority port-priority

CLI

Switch> (enable) set spantree portpri mod/num cost

 

5.4.5 Modifying port priority by VLAN

IOS

Switch(config-if)#spanning-tree [vlan vlan-list] port-priority port-priority

CLI

Switch> (enable) set spantree portvlanpri mod/num priority vlan-list

 

5.4.6 Modifying STP timers

IOS

Switch(config)#spanning-tree [vlan vlan-list] [hello-time seconds]

Switch(config)#spanning-tree [vlan vlan-list] [forward-time seconds]

Switch(config)#spanning-tree [vlan vlan-list] [max-age seconds]

CLI

Switch> (enable) set spantree hello interval [vlan]

Switch> (enable) set spantree fwddelay delay [vlan]

Switch> (enable) set spantree maxage agingtime [vlan]

Switch> (enable) set spantree root [secondary] [vlan-list] [dia diameter] [hello hellotime]

 

 

5.5.3 EtherChannel rules of the road

IOS

CLI

Switch> (enable) set port channel

 

5.5.4 Configuring Fast EtherChannel

IOS

Switch(config-if)#port group group number distribution |destination / source|

CLI

Switch> (enable) show port capabilities [mod_num[/port_num]]

Switch> (enable) set port channel mod_num/ports on | off | auto | desirable.

 

5.5.5 Configuring PortFast

IOS

Switch(config)#spanning-tree portfast

CLI

Switch> (enable) set spantree portfast [mod/num] [enable|disable]

 

5.5.6 Configuring UplinkFast

IOS

Switch(config)#spanning-tree uplinkfast [max-update-rate pkts-per-sec]

CLI

Switch> (enable) set spantree uplinkfast [enable|disable] [rate update-rate] [all-protocols off | on]

 

5.5.7 Configuring BackboneFast

IOS

CLI

Switch> (enable) set spantree backbonefast [enable|disable]

Switch> (enable) show spantree backbonefast