📖 What is Link Aggregation Control Protocol (LACP)?
An IEEE standard (802.3ad) protocol used to automatically negotiate and bundle multiple physical ports into a single logical EtherChannel.
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Sensei Says:
"LACP uses 'Active' and 'Passive' modes. To form a channel, at least one side must be Active. Active-Active works, but Passive-Passive will never form an EtherChannel."
📚 Certification: Certified Network Associate (200-301)
🔑 What are the Key Concepts of Link Aggregation Control Protocol (LACP)?
- ▸ Open standard protocol (IEEE 802.3ad / 802.1AX)
- ▸ Modes: Active (initiates) and Passive (listens)
- ▸ Supports up to 16 ports per bundle (8 active, 8 standby)
🎯 How does Link Aggregation Control Protocol (LACP) appear on the 200-301 Exam?
Configuring an EtherChannel between a Cisco switch and a third-party vendor switch.
Determining why an LACP channel failed to form when both sides are configured as Passive.
❓ Frequently Asked Questions
What happens if both sides of an LACP connection are configured as Passive?
The EtherChannel will not form because neither side is actively initiating the negotiation.
Is LACP Cisco-proprietary?
No, LACP is an open IEEE standard, unlike PAgP which is Cisco-proprietary.
Related Terms from Certified Network Associate
Link-State Advertisement (LSA)
Inside Local Address
User Datagram Protocol (UDP)
Virtual Routing and Forwarding (VRF)
Native VLAN
DTP (Dynamic Trunking Protocol)