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Network services features
Link aggregation
Ethernet link aggregation bundles multiple physical Ethernet links into one logical link, called an
aggregate link. Link aggregation has the following benefits:
•
Increased bandwidth beyond the limits of any single link. In an aggregate link, traffic is
distributed across the member ports.
•
Improved link reliability. The member ports dynamically back up one another. When a member
port fails, its traffic is automatically switched to other member ports.
Aggregation group
Link bundling is implemented through interface bundling. An aggregation group is a group of
Ethernet interfaces bundled together. These Ethernet interfaces are called member ports of the
aggregation group. Each aggregation group has a corresponding logical interface (called an
aggregate interface).
When you create an aggregate interface, the device automatically creates an aggregation group of
the same type and number as the aggregate interface. For example, when you create Layer 2
aggregate interface 1, Layer 2 aggregation group 1 is created.
You can assign Layer 2 Ethernet interfaces only to a Layer 2 aggregation group.
The port rate of an aggregate interface equals the total rate of its Selected member ports. Its duplex
mode is the same as that of the Selected member ports.
Aggregation states of member ports in an aggregation group
A member port in an aggregation group can be in any of the following aggregation states:
•
Selected
—A Selected port can forward traffic.
•
Unselected
—An Unselected port cannot forward traffic.
Operational key
When aggregating ports, the system automatically assigns each port an operational key based on
port information, such as port rate and duplex mode. Any change to this information triggers a
recalculation of the operational key.
In an aggregation group, all Selected ports have the same operational key.
Attribute configurations
To become a Selected port, a member port must have the same attribute configurations as the
aggregate interface.
Feature
Considerations
Port isolation
Indicates whether the port has joined an isolation group, and the isolation group
to which the port belongs.
VLAN
VLAN attribute configurations include:
•
Permitted VLAN IDs.
•
PVID.
•
VLAN tagging mode.
