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Link Aggregation
Unlike IOA Automated modes (Standalone and VLT modes), the IOA Programmable MUX (PMUX) can support multiple uplink
LAGs. You can provision multiple uplink LAGs. The I/O Aggregator auto-configures with link aggregation groups (LAGs) as
follows:
All uplink ports are automatically configured in a single port channel (LAG 128).
Server-facing LAGs are automatically configured if you configure server for link aggregation control protocol (LACP)-based
NIC teaming (Network Interface Controller (NIC) Teaming).
No manual configuration is required to configure Aggregator ports in the uplink or a server-facing LAG.
NOTE: Static LAGs are not supported on the SMUX Aggregator.
NOTE: In order to avoid loops, only disjoint VLANs are allowed between the uplink ports/uplink LAGs and uplink-to-uplink
switching is disabled.
Supported Modes
Standalone, VLT, PMUX, Stacking
Topics:
How the LACP is Implemented on an Aggregator
Link Aggregation Control Protocol (LACP)
Configuring Auto LAG
Configuring the Minimum Number of Links to be Up for Uplink LAGs to be Active
Optimizing Traffic Disruption Over LAG Interfaces On IOA Switches in VLT Mode
Preserving LAG and Port Channel Settings in Nonvolatile Storage
Enabling LACP link-fallback
Enabling the Verification of Member Links Utilization in a LAG Bundle
Monitoring the Member Links of a LAG Bundle
Verifying LACP Operation and LAG Configuration
Multiple Uplink LAGs with 10G Member Ports
How the LACP is Implemented on an Aggregator
The LACP provides a means for two systems (also called partner systems) to exchange information through dynamic
negotiations to aggregate two or more ports with common physical characteristics to form a link aggregation group.
NOTE: A link aggregation group is referred to as a port channel by the Dell Networking OS.
A LAG provides both load-sharing and port redundancy across stack units. An Aggregator supports LACP for auto-configuring
dynamic LAGs. Use CLI commands to display LACP information, clear port-channel counters, and debug LACP operation for
auto-configured LAG on an Aggregator.
The Dell Networking OS implementation of LACP is based on the standards specified in the IEEE 802.3: Carrier sense multiple
access with collision detection (CSMA/CD) access method and physical layer specifications.
LACP functions by constantly exchanging custom MAC protocol data units (PDUs) across local area network (LAN) Ethernet
links. The protocol packets are only exchanged between ports that you configure as LACP-capable.
NOTE:
In Standalone, VLT, and Stacking modes, you can configure a maximum of 16 members in port-channel 128. In
PMUX mode, you can have multiple port-channels with up to 16 members per channel.
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