dcb-ets(8) — Linux manual page


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

NAME         top

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

SYNOPSIS         top

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

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

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


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

       TC := { 0 .. 7 }

       PRIO := { 0 .. 7 }

DESCRIPTION         top

       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 traffic
       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. Recommendation values are named with a
       prefix reco-, while the configuration ones have plain names.

PARAMETERS         top

       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 keyword
       without further arguments. This instructs the tool to show the
       value of a given parameter. When no parameters are given, the
       tool shows the complete ETS configuration.

              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

       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
              priority 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 precedence 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,
              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 values 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         top

       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
       tc-bw 0:33 1:33 2:34 3:0 4:0 5:0 6:0 7:0

EXIT STATUS         top

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

SEE ALSO         top


REPORTING BUGS         top

       Report any bugs to the Network Developers mailing list
       <netdev@vger.kernel.org> where the development and maintenance is
       primarily done.  You do not have to be subscribed to the list to
       send a message there.

AUTHOR         top

       Petr Machata <me@pmachata.org>

COLOPHON         top

       This page is part of the iproute2 (utilities for controlling
       TCP/IP networking and traffic) project.  Information about the
       project can be found at 
       If you have a bug report for this manual page, send it to
       netdev@vger.kernel.org, shemminger@osdl.org.  This page was
       obtained from the project's upstream Git repository
       ⟨https://git.kernel.org/pub/scm/network/iproute2/iproute2.git⟩ on
       2021-04-01.  (At that time, the date of the most recent commit
       that was found in the repository was 2021-03-22.)  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to man-pages@man7.org

iproute2                     19 October 2020                  DCB-ETS(8)

Pages that refer to this page: dcb(8)