Configuring Link Bundling
- Entering no exits the configuration session and returns the router to EXEC mode without committing the
configuration changes.
- Entering cancel leaves the router in the current configuration session without exiting or committing the configuration
changes.
• Use the commit command to save the configuration changes to the running configuration file and remain within
the configuration session.
Information About Configuring Link Bundling
To configure link bundling, you must understand the following concepts:
IEEE 802.3ad Standard
The IEEE 802.3ad standard typically defines a method of forming Ethernet link bundles.
For each link configured as bundle member, the following information is exchanged between the systems that
host each end of the link bundle:
• A globally unique local system identifier
• An identifier (operational key) for the bundle of which the link is a member
• An identifier (port ID) for the link
• The current aggregation status of the link
This information is used to form the link aggregation group identifier (LAG ID). Links that share a common
LAG ID can be aggregated. Individual links have unique LAG IDs.
The system identifier distinguishes one router from another, and its uniqueness is guaranteed through the use
of a MAC address from the system. The bundle and link identifiers have significance only to the router
assigning them, which must guarantee that no two links have the same identifier, and that no two bundles
have the same identifier.
The information from the peer system is combined with the information from the local system to determine
the compatibility of the links configured to be members of a bundle.
The MAC address of the first link attached to a bundle becomes the MAC address of the bundle itself. The
bundle uses this MAC address until that link (the first link attached to the bundle) is detached from the bundle,
or until the user configures a different MAC address. The bundle MAC address is used by all member links
when passing bundle traffic. Any unicast or multicast addresses set on the bundle are also set on all the member
links.
We recommend that you avoid modifying the MAC address, because changes in the MAC address can
Note
affect packet forwarding.
Interface and Hardware Component Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.1.x
Information About Configuring Link Bundling
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