Manual: dcb-ets

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

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

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) in‐
       terface. 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
       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 configura‐
       tion.

       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 Al‐
	      gorithm.

       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 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 Selec‐
	      tion 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	 ac‐
	      cording to the weights set by tc-bw and reco-tc-bw, respectively.
	      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 allo‐
	      cation 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  where the development and maintenance
       is primarily done.  You do not have to be subscribed to the list to send a message there.

AUTHOR
       Petr Machata 

iproute2					       19 October 2020						  DCB-ETS(8)