Provided by: firehol-doc_3.1.7+ds-2_all bug


       firehol-dscp - set the DSCP field in the packet header


       dscp { value | class classid } chain rule-params


       The dscp helper command sets the DSCP field in the header of packets traffic, to allow QoS


              There is also a dscp parameter which allows matching DSCP values within  individual
              rules (see firehol-params(5)).

       Set  value  to a decimal or hexadecimal (0xnn) number to set an explicit DSCP value or use
       class classid to use an iptables(8) DiffServ class, such as EF,  BE,  CSxx  or  AFxx  (see
       iptables -j DSCP --help for more information).

       The chain will be used to find traffic to mark.  It can be any of the iptables(8) built in
       chains belonging to the mangle table.   The  chain  names  are:  INPUT,  FORWARD,  OUTPUT,
       PREROUTING and POSTROUTING.  The names are case-sensitive.

       The  rule-params 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.

       Any dscp commands will affect all traffic matched.  They must be declared before the first
       router or interface.


               # 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
               dscp class EF FORWARD proto tcp dport 25 dst


firehol(1) - FireHOL program

       • firehol.conf(5) - FireHOL configuration

       • firehol-params(5) - optional rule parameters

       • iptables(8)  (  -  administration  tool for
         IPv4 firewalls

       • ip6tables(8) ( - administration  tool  for
         IPv6 firewalls

       • ip(8) - show / manipulate routing, devices, policy routing and tunnels

       • FireHOL Website (

       • FireHOL Online PDF Manual (

       • FireHOL Online Documentation (

       • Linux Advanced Routing & Traffic Control HOWTO (


       FireHOL Team.