Lab na-07 - PAgP vs LACP

EtherChannel can be negotiated by two different protocols: Cisco's proprietary PAgP (Port Aggregation Protocol) or the IEEE standard LACP (Link Aggregation Control Protocol, 802.3ad). LACP is the modern default because it interoperates with everyone. PAgP only works between Cisco switches. This lab compares them side by side and shows when you might (rarely) still use PAgP.

What you will learn

• The two protocols and their key differences
• The mode keywords for each (LACP: active/passive; PAgP: desirable/auto)
• How to read show etherchannel summary to identify which protocol is in use
• The interoperability rule: you cannot mix PAgP on one end with LACP on the other
• When PAgP is still seen in production and why it is being phased out

What this lab does NOT cover

• Layer 3 EtherChannel (different config, same protocol options)
• Multi-chassis EtherChannel (vPC, MLAG, VSS)

Topology