Ieee 802.3Ad Standard; Non Revertive Behavior For Lacp Bundle Interface; Qos And Link Bundling - Cisco ASR 9000 Series Configuration Manuallines
L2vpn and ethernet services configuration guide
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Also See for ASR 9000 Series:
- Command reference manual (1138 pages) ,
- Routing configuration manual (702 pages) ,
- Reference manual (696 pages)
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IEEE 802.3ad Standard
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, this 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.
Bundle MAC addresses in the routers come from a set of reserved MAC addresses in the backplane. This
MAC address stays with the bundle as long as the bundle interface exists. The bundle uses this MAC address
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.
Note
We recommend that you avoid modifying the MAC address, because changes in the MAC address can affect
packet forwarding.
Non Revertive Behavior for LACP Bundle Interface
In LACP, by default, a higher priority port would become the active port after it becomes operational again.
To avoid this reversion, you can run the lacp non-revertive command. This configures the lower priority
port to continue as the active port even after the higher priority port is capable of being operational. This
avoids the traffic disruption that may happen in putting the currently active but lower priority port into standby
and diverting traffic through the higher priority port that is now capable of being operational.
QoS and Link Bundling
On the ingress direction, QoS is applied to the local instance of a bundle. Each bundle is associated with a set
of queues. QoS is applied to the various network layer protocols that are configured on the bundle.
On the egress direction, QoS is applied on the bundle with a reference to the member links. QoS is applied
based on the sum of the member bandwidths.
L2VPN and Ethernet Services Configuration Guide for Cisco ASR 9000 Series Routers, IOS XR Release 6.3.x
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Configuring Link Bundles
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