09-10-2012
Just reading the man page, but don't you need symmetrical rules to allow packets to flow both ways and make a tcp connection?
Man Page for iptables (linux Section 8) - The UNIX and Linux Forums After your tcp syn packet gets there, the tcp syn ack has to have a path back.
Pre is for packets outgoing from inside-net, post is for packets incoming from outside-net, and output is for locally gen packets. For a firewall host, one seems to need reciprocal Pre and Post, and for a local only client firewall, output and post.
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LEARN ABOUT SUNOS
tc-route
Route classifier in tc(8) Linux Route classifier in tc(8)
NAME
route - route traffic control filter
SYNOPSIS
tc filter ... route [ from REALM | fromif TAG ] [ to REALM ] [ classid CLASSID ] [ action ACTION_SPEC ]
DESCRIPTION
Match packets based on routing table entries. This filter centers around the possibility to assign a realm to routing table entries. For
any packet to be classified by this filter, a routing table lookup is performed and the returned realm is used to decide on whether the
packet is a match or not.
OPTIONS
action ACTION_SPEC
Apply an action from the generic actions framework on matching packets.
classid CLASSID
Push matching packets into the class identified by CLASSID.
from REALM
fromif TAG
Perform source route lookups. TAG is the name of an interface which must be present on the system at the time of tc invocation.
to REALM
Match if normal (i.e., destination) routing returns the given REALM.
EXAMPLES
Consider the subnet 192.168.2.0/24 being attached to eth0:
ip route add 192.168.2.0/24 dev eth0 realm 2
The following route filter will then match packets from that subnet:
tc filter add ... route from 2 classid 1:2
and pass packets on to class 1:2.
NOTES
Due to implementation details, realm values must be in a range from 0 to 255, inclusive. Alternatively, a verbose name defined in
/etc/iproute2/rt_realms may be given instead.
SEE ALSO
tc(8), ip-route(8)
iproute2 21 Oct 2015 Route classifier in tc(8)