Dell Networking 2048, Справочное руководство

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Data Center Bridging Commands
Default Configuration
By default, all the traffic classes are mapped to TCG 0. In the default
configuration, all the Traffic Classes are grouped as one Traffic Class Group
and TCG0 is configured as weighted round robin.
Command Mode
Global Config, Interface Configuration modes
User Guidelines
NOTE: This command is only available on N40xx series switches.
For a given Traffic Class, a value specified in Interface Configuration mode
only affects a single interface, whereas a change in Global Configuration
mode is applied to all interfaces. The Interface Configuration mode
command is only available on platforms that support independent per-port
class of service mappings. Ports that are configured to use the DCBX auto-
configuration roles (auto-up or auto-down) have their ETS settings
overridden. Only ports configured as DCBX manual role utilize the
configured ETS settings.
It is recommended that all strict priority traffic classes be mapped to a single
TCG.
Internally, frames are selected for transmission from the strict priority TCGs
first, then, once the constraints of the TCGs are satisfied, frames from the
WRR TCGs are selected for transmission. For example, grouping strict
priority assignments into TCG 1 and weighted assignments into TCG 0 will
result in all frames of the highest priority in TCG 1 being transmitted first,
then the next lower priority, et. seq. until no frames remain for transmission
in TCG 1. Then the scheduler will process frames from TCG 0, giving them
appropriate treatment based upon the weights, minimum bandwidth and
maximum bandwidth constraints.
Traffic class group 7 is reserved by the system for internal use.
Example
The following example demonstrates how to globally map priorities 1 and 2 to
TCG 1.
console(config)# classofservice traffic-class-group 1 1
console(config)# classofservice traffic-class-group 2 1
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