tc-fw(8) - phpMan

Firewall mark classifier in tc(8)    Linux   Firewall mark classifier in tc(8)
NAME
       fw - fwmark traffic control filter
SYNOPSIS
       tc filter ... fw [ classid CLASSID ] [ action ACTION_SPEC ]
DESCRIPTION
       the  fw filter allows one to classify packets based on a previously set
       fwmark by iptables.  If the masked value of the fwmark matches the fil-
       ter's masked handle, the filter matches. By default, all 32 bits of the
       handle and the fwmark are masked.  iptables allows one 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 fil-
       tering 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
       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
       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 ipta-
       bles statement marking packets coming in on eth0:
              iptables -t mangle -A PREROUTING -i eth0 -j MARK --set-mark 6
       Specific bits of the packet's fwmark  can  be  set  using  the  skbedit
       action. For example, to only set one bit of the fwmark without changing
       any other bit:
              tc filter add ... action skbedit mark 0x8/0x8
       The fw filter can then be used to match on this bit by masking the han-
       dle:
              tc filter add ... handle 0x8/0x8 fw action drop
       This is useful when different bits of the fwmark are assigned different
       meanings.
SEE ALSO
       tc(8), iptables(8), iptables-extensions(8), tc-skbedit(8)
iproute2                          21 Oct 2015Firewall mark classifier in tc(8)