EtherChannel Configuration | LAgP & PACP Protocol | CCNA 200-301

EtherChannel provides a way to prevent the need for Spanning Tree Protocol (STP). EtherChannel technology enables you, to bundle multiple physical interfaces into one logical channel to increase the bandwidth. It means when you configure EtherChannel all connected ports in sw2 will be forwarding data, and remove the block state. It means STP sees the bundle of links as a single interface.
 Specify the interfaces that you want to bundle together in one link by using the interface range choose the interfaces that you want to bundle.
 Create a port channel by using the channel-group identifier mode for example mode on command.
identifier for this IOS can be any number between 1, 255 and does not have to match the other switch. The mode is either on or one of the PAgP or LACP modes. As I said in previous video, Port aggregation protocol use desirable and auto mode, and link aggregation control protocol use active and passive mode.
 Enter interface configuration mode for the new port channel with the interface port-channel identifier command. identifier is the same number used with the channel-group command.
 Configure the trunking and VLAN settings.
For Troubleshooting EtherChannel
All interfaces within an EtherChannel must have the same configuration. Same speed same duplex mode. Specify Native and allowed VLANs on trunk ports, and access VLAN on access ports:
Assign all ports in the EtherChannel to the same VLAN or configure them as trunks. Ports with different native VLANs cannot form an EtherChannel.
When configuring a trunk on an EtherChannel, verify the trunking mode on the EtherChannel. verify that the trunking configuration is the same on all interfaces.
An EtherChannel supports the same allowed range of VLANs on all the ports. If the allowed range of VLANs is not the same, the ports do not form an EtherChannel even when PAgP is set to auto or desirable mode.
The dynamic negotiation options for PAgP and LACP must be compatibly configured on both ends of the EtherChannel.
Configuring the on keyword on one switch and desirable, auto, active, or passive on the other switch.
Remember The on keyword does not enable PAgP or LACP. Both switches should be configured on one of the acceptable PAgP or LACP modes.