Aggregated Ethernet Interfaces Overview
Link aggregation of Ethernet interfaces is defined in the IEEE 802.3ad standard. The Junos implementation of 802.3ad balances traffic across the member links within an aggregated Ethernet bundle based on the Layer 3 information carried in the packet. This implementation uses the same load-balancing algorithm used for per-packet load balancing. For information about per-packet load balancing, see the Junos Routing Protocols Configuration Guide.
 | Note: For information about configuring circuit cross-connects over aggregated Ethernet, see Circuit and Translational Cross-Connects Overview. |
Platform Support for Aggregated Ethernet Interfaces
You configure an aggregated Ethernet virtual link by specifying the link number as a physical device and then associating a set of ports that have the same speed and are in full-duplex mode. The physical interfaces can be Fast Ethernet, Tri-Rate Ethernet copper, Gigabit Ethernet, Gigabit Ethernet IQ, 10-Gigabit Ethernet IQ, Gigabit Ethernet IQ2 and IQ2-E, or 10-Gigabit Ethernet IQ2 and IQ2-E. Generally, you cannot use a combination of these interfaces within the same aggregated link; however, you can combine Gigabit Ethernet and Gigabit Ethernet IQ interfaces in a single aggregated Ethernet bundle.
The following routers support a maximum of 16 physical interfaces per single aggregated Ethernet bundle:
- M120
- M320
- MX960
- MX480
- MX240
- All T Series routers
All other routers support a maximum of 8 physical interfaces per aggregated Ethernet bundle.
Aggregated Ethernet interfaces can use interfaces from different FPCs, DPCs, or PICs.
Configuration Guidelines for Aggregated Ethernet Interfaces
Simple filters are not supported for interfaces in aggregated Ethernet bundles:
- in M Series routers, simple filters are supported in Gigabit Ethernet Enhanced Intelligent Queuing interfaces only, except when the interface is part of an aggregated Ethernet bundle.
- in MX Series routers, simple filters are supported in Enhanced Queuing Dense Port Concentrator (EQ DPC) interfaces only, except when the interface is part of an aggregated Ethernet bundle.
For more information about simple filters, see the Junos Class of Service Configuration Guide.
On the aggregated bundle, no IQ-specific capabilities such as MAC accounting, VLAN rewrites, and VLAN queuing are available. For more information about IQ-specific capabilities, see Gigabit Ethernet Accounting and Policing Overview.
Aggregated Ethernet interfaces can be either tagged or untagged, with LACP enabled or disabled. Aggregated Ethernet interfaces on MX Series routers support the configuration of flexible-vlan-tagging, native-vlan-id, and on dual-tagged frames, which consist of the following configuration statements:
In all cases, you must set the number of aggregated Ethernet interfaces on the chassis. You can also set the link speed and the minimum links in a bundle.
