# phpman > man > tc-fw(8)

Firewall mark classifier in [tc(8)](https://www.chedong.com/phpMan.php/man/tc/8/markdown)               Linux              Firewall mark classifier in [tc(8)](https://www.chedong.com/phpMan.php/man/tc/8/markdown)



## NAME
       fw - fwmark traffic control filter

## SYNOPSIS
       **tc** **filter** ... **fw** [ **classid** _CLASSID_ ] [ **action** _ACTION_SPEC_ ]

## DESCRIPTION
       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 con‐
       venient  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
       **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 **iptables** statement marking
       packets coming in on eth0:

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

## SEE ALSO
       [**tc**(8)](https://www.chedong.com/phpMan.php/man/tc/8/markdown), [**iptables**(8)](https://www.chedong.com/phpMan.php/man/iptables/8/markdown), [**iptables-extensions**(8)](https://www.chedong.com/phpMan.php/man/iptables-extensions/8/markdown)



iproute2                                     21 Oct 2015           Firewall mark classifier in [tc(8)](https://www.chedong.com/phpMan.php/man/tc/8/markdown)