Dell S4048-ON, Руководство по настройке

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Null Interfaces
The Null interface is another virtual interface. There is only one Null interface. It is always up, but no traffic is transmitted through this
interface.
To enter INTERFACE mode of the Null interface, use the following command.
• Enter INTERFACE mode of the Null interface.
CONFIGURATION mode
interface null 0
The only configurable command in INTERFACE mode of the Null interface is the
ip unreachable
command.
Port Channel Interfaces
Port channel interfaces support link aggregation, as described in IEEE Standard 802.3ad.
This section covers the following topics:
• Port Channel Definition and Standards
• Port Channel Benefits
• Port Channel Implementation
• Configuration Tasks for Port Channel Interfaces
Port Channel Definition and Standards
Link aggregation is defined by IEEE 802.3ad as a method of grouping multiple physical interfaces into a single logical interface—a link
aggregation group (LAG) or port channel.
A LAG is “a group of links that appear to a MAC client as if they were a single link” according to IEEE 802.3ad. In Dell Networking OS,
a LAG is referred to as a port channel interface.
A port channel provides redundancy by aggregating physical interfaces into one logical interface. If one physical interface goes down
in the port channel, another physical interface carries the traffic.
Port Channel Benefits
A port channel interface provides many benefits, including easy management, link redundancy, and sharing.
Port channels are transparent to network configurations and can be modified and managed as one interface. For example, you
configure one IP address for the group and that IP address is used for all routed traffic on the port channel.
With this feature, you can create larger-capacity interfaces by utilizing a group of lower-speed links. For example, you can build a 50-
Gigabit interface by aggregating five 10-Gigabit Ethernet interfaces together. If one of the five interfaces fails, traffic is redistributed
across the remaining interfaces.
Port Channel Implementation
Dell Networking OS supports static and dynamic port channels.
• Static — Port channels that are statically configured.
• Dynamic — Port channels that are dynamically configured using the link aggregation control protocol (LACP). For details, see
Link Aggregation Control Protocol (LACP) .
There are 128 port-channels with 16 members per channel.
As soon as you configure a port channel, Dell Networking OS treats it like a physical interface. For example, IEEE 802.1Q tagging is
maintained while the physical interface is in the port channel.
Interfaces
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