.TH DCB-PFC 8 "31 October 2020" "iproute2" "Linux"

.SH NAME

dcb-pfc \- show / manipulate PFC (Priority-based Flow Control) settings of

the DCB (Data Center Bridging) subsystem

.SH SYNOPSIS

.sp

.ad l

.in +8

.ti -8

.B dcb

.RI "[ " OPTIONS " ] "

.B pfc

.RI "{ " COMMAND " | " help " }"

.sp

.ti -8

.B dcb pfc show dev

.RI DEV

.RB "[ " pfc-cap " ]"

.RB "[ " prio-pfc " ]"

.RB "[ " macsec-bypass " ]"

.RB "[ " delay " ]"

.RB "[ " requests " ]"

.RB "[ " indications " ]"

.ti -8

.B dcb pfc set dev

.RI DEV

.RB "[ " prio-pfc " " \fIPFC-MAP " ]"

.RB "[ " macsec-bypass " { " on " | " off " } ]"

.RB "[ " delay " " \fIINTEGER\fR " ]"

.ti -8

.IR PFC-MAP " := [ " PFC-MAP " ] " PFC-MAPPING

.ti -8

.IR PFC-MAPPING " := { " PRIO " | " \fBall " }" \fB:\fR "{ "

.IR \fBon\fR " | " \fBoff\fR " }"

.ti -8

.IR PRIO " := { " \fB0\fR " .. " \fB7\fR " }"

.SH DESCRIPTION

.B dcb pfc

is used to configure Priority-based Flow Control attributes through Linux

DCB (Data Center Bridging) interface. PFC permits marking flows with a

certain priority as lossless, and holds related configuration, as well as

PFC counters.

.SH PARAMETERS

For read-write parameters, the following describes only the write direction,

i.e. as used with the \fBset\fR command. For the \fBshow\fR 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 PFC configuration.

.TP

.B pfc-cap

A read-only property that shows the number of traffic classes that may

simultaneously support PFC.

.TP

.B requests

A read-only count of the sent PFC frames per traffic class. Only shown when

-s is given, or when requested explicitly.

.TP

.B indications

A read-only count of the received PFC frames per traffic class. Only shown

when -s is given, or when requested explicitly.

.TP

.B macsec-bypass \fR{ \fBon\fR | \fBoff\fR }

Whether the sending station is capable of bypassing MACsec processing when

MACsec is disabled.

.TP

.B prio-pfc \fIPFC-MAP

\fIPFC-MAP\fR uses the array parameter syntax, see

.BR dcb (8)

for details. Keys are priorities, values are on / off indicators of whether

PFC is enabled for a given priority.

.TP

.B delay \fIINTEGER

The allowance made for round-trip propagation delay of the link in bits.

The value shall be 0..65535.

.SH EXAMPLE & USAGE

Enable PFC on priorities 6 and 7, leaving the rest intact:

.P

# dcb pfc set dev eth0 prio-pfc 6:on 7:on

Disable PFC of all priorities except 6 and 7, and configure delay to 4096

bits:

.P

# dcb pfc set dev eth0 prio-pfc all:off 6:on 7:on delay 0x1000

Show what was set:

.P

# dcb pfc show dev eth0

.br

pfc-cap 8 macsec-bypass off delay 4096

.br

prio-pfc 0:off 1:off 2:off 3:off 4:off 5:off 6:on 7:on

.SH EXIT STATUS

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

.SH SEE ALSO

.BR dcb (8)

.SH REPORTING BUGS

Report any bugs to the Network Developers mailing list

.B <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.

.SH AUTHOR

Petr Machata <me@pmachata.org>