1. CCNP-SWITCHING 300-115 Mohamed Samir YouTube channel Double CCIEs #27042(R/S&SP)

2. Part III Working with Redundant Links

3. Spanning-Tree Configuration & design

4. SW2
SW1
FA0/1
FA0/1
FA0/11
FA0/2
FA0/2
FA0/11
FA0/1
FA0/1
FA0/2
FA0/2
SW4
SW3

5. Root bridge

7. Bottleneke
To prevent the surprises
Configure one switch as a root bridge in a determined fashion.
Configure another switch as a secondary root bridge, in case of a primary root bridge failure.

8. Root Bridge Configuration
Switch(config)# spanning-tree vlan vlan-list priority bridge-priority
Switch(config)# spanning-tree vlan 5, priority 4096
Switch(config)# spanning-tree vlan vlan-id root {primary |secondary} [diameter diameter]
24,  & secondary >>> 28,672

9. Tuning the Root Path Cost
Switch (config-if)# spanning-tree [vlan vlan-id] cost cost
Tuning the Port ID
Switch(config)# interface gigabitethernet 2/0/44
Switch(config-if)# spanning-tree vlan 10,100 port-priority 64

10. Modifying STP Timers
Switch(config)# spanning-tree [vlan vlan-id] hello-time seconds
Switch(config)# spanning-tree [vlan vlan-id] forward-time seconds
Switch(config)# spanning-tree [vlan vlan-id] max-age seconds
Automatically Configuring STP Timers
Switch(config)# spanning-tree vlan vlan-list root {primary | secondary} [diameter
diameter [hello-time hello-time]]

11. Redundant Link Convergence
PortFast: Access Layer Nodes
30 sec spanning tree + 20 sec Port Aggregation Protocol (PAgP)
Switch(config)# spanning-tree portfast default
show spanning-tree interface gigabitethernet 1/0/10 portfast
Switch(config)# interface type member/module/number
Switch(config-if)# switchport host
switchport mode will be set to access
spanning-tree portfast will be enabled
channel group will be disabled

12. UplinkFast: Access Layer Uplinks
Switch(config)# spanning-tree uplinkfast [max-update-rate pkts-per-second]
0100.0ccd.cdcd
The default is 150 packets per second (pps),
Switch# show spanning-tree uplinkfast

13. BackboneFast: Redundant Backbone Paths
Switch(config)# spanning-tree backbonefast
reduce the maximum
convergence delay only from 50 to 30 seconds
Switch# show spanning-tree backbonefast

14. Any questions ?

15. Thank you for your time ! 
شكرا
جزاكم الله خير