.\" Automatically generated by Pandoc 3.1.3
.nh
.\"
.\" Define V font for inline verbatim, using C font in formats
.\" that render this, and otherwise B font.
.ie "\f[CB]x\f[]"x" \{\
. ftr V B
. ftr VI BI
. ftr VB B
. ftr VBI BI
.\}
.el \{\
. ftr V CR
. ftr VI CI
. ftr VB CB
. ftr VBI CBI
.\}
.TH "firehol-dscp" "5" "Built 30 Mar 2024" "FireHOL Reference" "3.1.7"
.hy
.SH NAME
.PP
firehol-dscp - set the DSCP field in the packet header
.SH SYNOPSIS
.PP
dscp { \f[I]value\f[R] | class \f[I]classid\f[R] } \f[I]chain\f[R]
\f[I]rule-params\f[R]
.SH DESCRIPTION
.PP
The \f[V]dscp\f[R] helper command sets the DSCP field in the header of
packets traffic, to allow QoS shaping.
.RS
.PP
\f[B]Note\f[R]
.PP
There is also a \f[V]dscp\f[R] parameter which allows matching DSCP
values within individual rules (see firehol-params(5)).
.RE
.PP
Set \f[I]value\f[R] to a decimal or hexadecimal (0xnn) number to set an
explicit DSCP value or use \f[V]class\f[R] \f[I]classid\f[R] to use an
iptables(8) DiffServ class, such as EF, BE, CSxx or AFxx (see
\f[V]iptables -j DSCP --help\f[R] for more information).
.PP
The \f[I]chain\f[R] will be used to find traffic to mark.
It can be any of the iptables(8) built in chains belonging to the
\f[V]mangle\f[R] table.
The chain names are: INPUT, FORWARD, OUTPUT, PREROUTING and POSTROUTING.
The names are case-sensitive.
.PP
The \f[I]rule-params\f[R] define a set of rule parameters to match the
traffic that is to be marked within the chosen chain.
See firehol-params(5) for more details.
.PP
Any \f[V]dscp\f[R] commands will affect all traffic matched.
They must be declared before the first router or interface.
.SH EXAMPLES
.IP
.nf
\f[C]

 # set DSCP field to 32, packets sent by the local machine
 dscp 32 OUTPUT

 # set DSCP field to 32 (hex 20), packets routed by the local machine
 dscp 0x20 FORWARD

 # set DSCP to DiffServ class EF, packets routed by the local machine
 #              and destined for port TCP/25 of 198.51.100.1
 dscp class EF FORWARD proto tcp dport 25 dst 198.51.100.1
\f[R]
.fi
.SH SEE ALSO
.IP \[bu] 2
firehol(1) - FireHOL program
.IP \[bu] 2
firehol.conf(5) - FireHOL configuration
.IP \[bu] 2
firehol-params(5) - optional rule parameters
.IP \[bu] 2
iptables(8) (http://ipset.netfilter.org/iptables.man.html) -
administration tool for IPv4 firewalls
.IP \[bu] 2
ip6tables(8) (http://ipset.netfilter.org/ip6tables.man.html) -
administration tool for IPv6 firewalls
.IP \[bu] 2
ip(8) - show / manipulate routing, devices, policy routing and tunnels
.IP \[bu] 2
FireHOL Website (http://firehol.org/)
.IP \[bu] 2
FireHOL Online PDF Manual (http://firehol.org/firehol-manual.pdf)
.IP \[bu] 2
FireHOL Online Documentation (http://firehol.org/documentation/)
.IP \[bu] 2
Linux Advanced Routing & Traffic Control HOWTO (http://lartc.org/howto/)
.SH AUTHORS
FireHOL Team.