phpman > man > dcb-ets(8)

DCB-ETS(8)                                      Linux                                     DCB-ETS(8)



NAME
       dcb-ets  -  show / manipulate ETS (Enhanced Transmission Selection) settings of the DCB (Data
       Center Bridging) subsystem

SYNOPSIS
       dcb [ OPTIONS ] ets { COMMAND | help }


       dcb ets show dev DEV [ willing ] [ ets-cap ] [ cbs ] [ tc-tsa ] [ reco-tc-tsa ] [ pg-bw ] [
               tc-bw ] [ reco-tc-bw ] [ prio-tc ] [ reco-prio-tc ]

       dcb ets set dev DEV [ willing { on | off } ] [ { tc-tsa | reco-tc-tsa } TSA-MAP ] [ { pg-bw |
               tc-bw | reco-tc-bw } BW-MAP ] [ { prio-tc | reco-prio-tc } PRIO-MAP ]

       TSA-MAP := [ TSA-MAP ] TSA-MAPPING

       TSA-MAPPING := { TC | all }:{ strict | cbs | ets | vendor }

       BW-MAP := [ BW-MAP ] BW-MAPPING

       BW-MAPPING := { TC | all }:INTEGER

       PRIO-MAP := [ PRIO-MAP ] PRIO-MAPPING

       PRIO-MAPPING := { PRIO | all }:TC

       TC := { 0 .. 7 }

       PRIO := { 0 .. 7 }


DESCRIPTION
       dcb ets is used to configure Enhanced Transmission Selection attributes through Linux DCB
       (Data Center Bridging) interface. ETS permits configuration of mapping of priorities to traf‐
       fic classes, traffic selection algorithm to use per traffic class, bandwidth allocation, etc.

       Two DCB TLVs are related to the ETS feature: a configuration and recommendation values. Rec‐
       ommendation values are named with a prefix reco-, while the configuration ones have plain
       names.


PARAMETERS
       For read-write parameters, the following describes only the write direction, i.e. as used
       with the set command. For the show command, the parameter name is to be used as a simple key‐
       word without further arguments. This instructs the tool to show the value of a given parame‐
       ter. When no parameters are given, the tool shows the complete ETS configuration.


       ets-cap
              A read-only property that shows the number of supported ETS traffic classes.


       cbs    A read-only property that is enabled if the driver and the hardware support the CBS
              Transmission Selection Algorithm.


       willing { on | off }
              Whether local host should accept configuration from peer TLVs.


       prio-tc PRIO-MAP
       reco-prio-tc PRIO-MAP
              PRIO-MAP uses the array parameter syntax, see dcb(8) for details. Keys are priorities,
              values are traffic classes. For each priority sets a TC where traffic with that prior‐
              ity is directed to.


       tc-tsa TSA-MAP
       reco-tc-tsa TSA-MAP
              TSA-MAP uses the array parameter syntax, see dcb(8) for details. Keys are TCs, values
              are Transmission Selection Algorithm (TSA) keywords described below. For each TC sets
              an algorithm used for deciding how traffic queued up at this TC is scheduled for
              transmission. Supported TSAs are:

              strict - for strict priority, where traffic in higher-numbered TCs always takes prece‐
              dence over traffic in lower-numbered TCs.
              ets - for Enhanced Traffic Selection, where available bandwidth is distributed among
              the ETS-enabled TCs according to the weights set by tc-bw and reco-tc-bw, respec‐
              tively.
              cbs - for Credit Based Shaper, where traffic is scheduled in a strict manner up to the
              limit set by a shaper.
              vendor - for vendor-specific traffic selection algorithm.


       tc-bw BW-MAP
       reco-tc-bw BW-MAP
              BW-MAP uses the array parameter syntax, see dcb(8) for details. Keys are TCs, values
              are integers representing percent of available bandwidth given to the traffic class in
              question. The value should be 0 for TCs whose TSA is not ets, and the sum of all val‐
              ues shall be 100. As an exception to the standard wording, a configuration with no ets
              TCs is permitted to sum up to 0 instead.


       pg-bw BW-MAP
              The precise meaning of pg-bw is not standardized, but the assumption seems to be that
              the same scheduling process as on the transmit side is applicable on receive side as
              well, and configures receive bandwidth allocation for ets ingress traffic classes
              (priority groups).


EXAMPLE & USAGE
       Configure ETS priomap in a one-to-one fashion:


       # dcb ets set dev eth0 prio-tc 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7

       Set TSA and transmit bandwidth configuration:


       # dcb ets set dev eth0 tc-tsa all:strict 0:ets 1:ets 2:ets \
                              tc-bw all:0 0:33 1:33 2:34

       Show what was set:


       # dcb ets show dev eth0 prio-tc tc-tsa tc-bw
       prio-tc 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
       tc-tsa 0:ets 1:ets 2:ets 3:strict 4:strict 5:strict 6:strict 7:strict
       tc-bw 0:33 1:33 2:34 3:0 4:0 5:0 6:0 7:0


EXIT STATUS
       Exit status is 0 if command was successful or a positive integer upon failure.


SEE ALSO
       dcb(8)


REPORTING BUGS
       Report any bugs to the Network Developers mailing list <netdev AT vger.org> where the de‐
       velopment and maintenance is primarily done.  You do not have to be subscribed to the list to
       send a message there.


AUTHOR
       Petr Machata <me AT pmachata.org>



iproute2                                   19 October 2020                                DCB-ETS(8)