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 per-
formed 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)
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