Let's begin the lab for configuring EtherChannel EtherChannel is the term that uses Cisco to aggregate links Between S1 and S3 is used Port Aggregation Protocol (PAgP), Cisco propietary With two 100Mbps links you will have a link with 200Mbps, even up to eight channels Link Aggregation Control Protocol (LACP) from IEEE compatible with other vendors We will configure both, LACP and PAgP Build the topology Addressing table Step 1 and Step 2 area ready these configurations are basic and were made in other labs, so I will not do it Configure vlan 99 and its name Management and vlan 10 with its name Staff configure switch ports and ip addresses shutdown all unused ports configure the ip addresses of PCs Part 2 Configure PAgP Between S1 and S3 Use the ports fa0/3 and f0/4 on S1 and S3 use channel group 1, but before I recommend to preparing these interfaces as a trunk on vlan 99 if you see the available modes channel group create the group 1 auto and desirable modes are used on PAgP auto mode will wait for the other side of the link is configured as PAgP desirable will obligatorily activate using PAgP and see if the other side of the link is capable of using PAgP auto is waiting and desirable is activating port channel 1 was created enable interfaces same way on S3 mode auto in this side of the link port channel 1 was created Packet TRacer doesn't support this command (show run interface fa0/3) member of bundle Po1 use show etherchannel summary on S1 group 1, Po1, Protocol PAgP, ports fa0/3 and f0/4 on S3, look at these messages, NATIVE VLAN MISMATCH and you can fix them group 1, Po1, Protocol PAgP, ports fa0/3 and f0/4 What do the flags, SU and P, indicate in the Ethernet summary? The flag S indicates that the port-channel is a Layer 2 EtherChannel. The U flag indicates that the EtherChannel is in use. The flag P indicates that the ports are bundled in a port-channel. configure trunk ports on S1 configure new port-channel 1 on S3 before the NATIVE VLAN MISMATCH message appeared and indicated the inconsistency of the native vlan and now it will just restore the consistency of native vlans you need to configure the physical interfaces first and then configure the port channel interface too use show running-config command there are the ports fa0/3 and fa0/4 configurations mode trunk on vlan 99 channel-group 1 mode auto the new port created port-channel 1, mode trunk on vlan 99 on S1 physical interfaces and new port-channel use show interfaces trunk commnad port Po1, mode on, native vlan 99 use show spanning-tree command for vlan 1 port Po1 is designated, status forwarding, cost 9 the port channel cost is lower than the ethernet port fastethernet cost is 19 and port channel cost is 9 priority number 128.28 for vlan 10 port fa0/6 is designated, status forwarding, cost 19 and priority number is 128.6 port Po1 is designated, status forwarding, cost 9 and priority number 128.28 vlan 99 only show the Po1 port Configure LACP is an open source protocol for link aggregation developed by the IEEE links from S1 to S2 and S2 to S3 are LACP test a ping from S1 to S3 ping was sucessful configure LACP betewn S1 and S2 configure the physical interfaces for LACP there are two modes: active and passive active is analog to desirable and passive is analog to auto active searchs on the other side of the link a port capable to use LACP and passive is waiting to be detected port channel 2 is created on S2 the same process MISMATCH NATIVE VLAN message to fix this configure the new port channels port channel is using the native vlan 1 but must be the native vlan 99
