tc-fw(8) — Linux manual page


Firewall mark classifier in tc(8) LinuxFirewall mark classifier in tc(8)

NAME         top

       fw - fwmark traffic control filter

SYNOPSIS         top

       tc filter ... fw [ classid CLASSID ] [ action ACTION_SPEC ]

DESCRIPTION         top

       the fw filter allows to classify packets based on a previously
       set fwmark by iptables.  If it is identical to the filter's
       handle, the filter matches.  iptables allows to mark single
       packets with the MARK target, or whole connections using
       CONNMARK.  The benefit of using this filter instead of doing the
       heavy-lifting with tc itself is that on one hand it might be
       convenient to keep packet filtering and classification in one
       place, possibly having to match a packet just once, and on the
       other users familiar with iptables but not tc will have a less
       hard time adding QoS to their setups.

OPTIONS         top

       classid CLASSID
              Push matching packets to the class identified by CLASSID.

       action ACTION_SPEC
              Apply an action from the generic actions framework on
              matching packets.

EXAMPLES         top

       Take e.g. the following tc filter statement:

              tc filter add ... handle 6 fw classid 1:1

       will match if the packet's fwmark value is 6.  This is a sample
       iptables statement marking packets coming in on eth0:

              iptables -t mangle -A PREROUTING -i eth0 -j MARK --set-mark 6

SEE ALSO         top

       tc(8), iptables(8), iptables-extensions(8)

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 
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       obtained from the project's upstream Git repository
       ⟨⟩ on
       2021-08-27.  (At that time, the date of the most recent commit
       that was found in the repository was 2021-08-18.)  If you
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iproute2                       21 Oct 20F1i5rewall mark classifier in tc(8)

Pages that refer to this page: tc(8)