Untitled

Other services

1. PortFast and BPDU Guard

   • PortFast – A feature on Cisco switches that tells a port to bypass the STP Listening and Learning states
   • BPDU Guard – Places a switchport, configured for PortFast, in the ErrDisable state, if a BPDU is received on that port
   • SwitchA(config)#int gig 1/0/13 SwitchA(config-if)#spanning-tree portfast SwitchA(config-if)#spanning-tree bpduguard enable Do a shutdown, no shutdown to bring out of ErrDisable state
   • Globally turn on PortFast for ports that aren’t trunking SwitchA(config)#spanning-tree portfast bpduguard default SwitchA(config)#spanning-tree portfast default

2. EtherChannel

   • 1. Bundle together multiple physical links
   • 2. Alllows higher bandwidth between switches
   • 3. Provides load-balancing
   • 4. Creates redundant links
   • Load-balancing Algorithms
     • 2. Destination IP
     • 3, Destination MAC
     • 4. Combination of Source IP and Destination IP
     • 1. Combination of Source and Destination MAC
     • 6. Source IP
     • 5. Source MAC
   • EtherChannel Port Options
     • Link Aggregation Protocols
       • PAgP: Port Aggregation Protocol
         • PAgP Port Negotiation
           • On – Not sending out PAgP frames, telling ports to be channel
           • Desirable – Willing to negotiate, willing to initiate
           • Auto – Not sending PAgP frames, willing to receive frames
           • Channel Mode – On
             • Other side – On Channel formed? Yes Other side – Auto Channel formed? No Other side – Desirable Channel formed? No
           • Channel Mode – Auto
             • Other side – On Channel formed? No Other side – Auto Channel formed? No Other side – Desirable Channel formed? Yes
           • Channel Mode – Desirable
             • Other side – On Channel formed? No Other side – Auto Channel formed? Yes Other side – Desirable Channel formed? Yes
       • LACP: Link Aggregation Control Protocol
         • LACP Port Negotiation
           • On – Similar to on
           • Passive – Similar to Auto
           • Active – Similar to Desirable
           • Channel Mode – On
             • Other side – On Channel formed? Yes Other side – Passive Channel formed? No Other side – Active Channel formed? No
           • Channel Mode – Passive
             • Other side – On Channel formed? No Other side – Passive Channel formed? No Other side - Active Channel formed? Yes
           • Channel Mode – Active
             • Other side – On Channel formed? No Other side – Passive Channel formed? Yes Other side – Active Channel formed? Yes
   • EtherChannel Configuration and Verification
     • Speed and duplex must be the same
     • Assigned to the same VLAN
     • SwitchA(config)#int range fa 1/0/1 – 2 SwitchA(config-if-range)#speed auto SwitchA(config-if-range)#duplex auto SwitchA(config-if-range)#mdix auto SwitchA(config-if-range)#channel-group 1 mode desirable (active, auto, desirable, on, passive) SwitchA(config-if-range)#int port-channel 1 SwitchA(config-if)#switchport trunk encapsulation dot1q SwitchA(config-if)#switchport mode trunk
     • SwitchB(config)#int range gig 0/9 – 10 SwitchB(config-if-range)#speed auto SwitchB(config-if-range)#duplex auto SwitchB(config-if-range)#mdix auto SwitchB(config-if-range)#channel-group 1 mode desirable SwitchB(config-if#int port-channel 1 SwitchB(config-if)#switchport trunk encapsulation dot1q SwitchB(config-if#switchport mode trunk SwitchB#show int trunk
     • Troubleshooting EtherChannel issues
       • SwitchA#show int port-channel 1 SwitchA#show etherchannel summary SwitchA#show etherchannel port-channel SwitchA#show etherchannel load-balance SwitchA(config)#port-channel load-balance src-dst-ip