EtherChannel

EtherChannel

• Cisco supports 3 types of EtherChannel.
• Mult chassis EtherChannel (MCEC).
• Stack wise (VSS and VPC)

• EtherChannel has two major components
• Port Channel interface (logical component)
• Member Interfaces (Physical interface part of the bundle)

• EtherChannel can be configured in three ways.
• Port Aggregation Protocol (LACP) IEEE.
• Link Aggregation Protocol (PAgP) - Cisco proprietary.
• No protocol (Static) mode On.

• PAgP
• Auto and Desirable
• Auto mode passively waits for the EtherChannel to Form
• Desirable actively tries to establish the EtherChannel.
• Auto - Auto (no EtherChannel)
• Auto - Desirable (Form and EtherChannel)
• Desirable - Desirable (Form and EtherChannel)

• LACP
• Passive and Active
• Passive mode passively waits for the EtherChannel to form
• Active mode actively tries to establish EtherChannel
• Passive - Passive (No channel)
• Passive - Active (Form and EtherChannel)
• Active - Active (Form and EtherChannel)
  
  
• EtherChannel misconfiguration guard
  
• This a feature used by STP
• Use the global command spanning-tree etherchannel guard misconfig to activate it.
• Use show spanning-tree command to check if it's enabled. See the example below.
  

SW1#sho spanning-tree summary | in Chan
EtherChannel misconfig guard            is enabled