Link aggregation control protocol: LACP belongs to the IEEE standard, technically explains as 802.3 ad but newly it was explained as 802.1AX for the purpose of LAN and MAN. The functioning of Link aggregation protocol is similar to port aggregation protocol along with EthernetChannel because it applies to multiple owner environments and it works on cisco devices as well. One of the benefits in LACP is if the present working active link fails the standby or disaster recovery link will come into action.
We have three modes in Link aggregation control protocol:
- On: channel can be created without negotiation which means no LACP packets are transferred between them to create a channel establishment.
- Active: Active mode asks the other switch that can you involve in Which means the interface will be in the state of active negotiating (initiates) i.e., sends LACP packets to the interface to establish the channel
- Passive: passive mode waits at the end to accepts the packets for channel creation but passive mode never initiates sending packets to other switches.
The on mode is the same for the two protocols because the EthernetChannel configuration can be done statically or unconditionally. So, it can be done without dynamic negotiation
First, we need to configure logical ethernet channel interface:
- Switch # configure terminal
- Switch (config) # interface port-channel 5
After that, they need to add the ports and mentioning the LACP modes for them.
Also, read…
- What is EtherChannel PAgP and LACP Modes
- Difference between Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP)
LACP Active mode: This mode makes a port into an active negotiating state that it will make the port into initiating negotiating with other porst as well by sending packets (LACP)
Configuration:
- Switch # configure terminal
- Switch (config)# interface FastEthernet 0/1
- Switch (config)# channel-group 5 mode active
- If the ports are bundled or need to check then use this command-line interface: Switch# show ethernet channel summary
LACP Passive mode: This port makes it into a passive negotiating state that makes or responds to LACP packets that it receives but does not initiate the negotiation of LACP.
Configuration:
- Switch # configure terminal
- Switch (config)# interface FastEthernet 0/1
- Switch (config)# channel-group 5 mode passive
- If the ports are bundled or need to check then use this command-line interface: Switch# show ethernet channel summary
LACP On mode: channel can be created without negotiation which means no LACP packets are transferred between them to create a channel establishment
Configuration:
- Switch # configure terminal
- Switch (config)# interface FastEthernet 0/1
- Switch (config)# channel-group 5 modes on
- If the ports are bundled or need to check then use this command-line interface: Switch# show ethernet channel summary
Download How to configure EtherChannel Link Aggregation Control Protocol (LACP) in Cisco Switches in pdf – Click here