Generic actions in tc(8) Linux Generic actions in tc(8)
NAME
gact - generic action
SYNOPSIS
tc ... action gact CONTROL [ RAND ] [ INDEX ]
CONTROL := { reclassify | drop | continue | pass | pipe |
goto chain CHAIN_INDEX |
jump JUMP_COUNT }
RAND := random RANDTYPE CONTROL VAL
RANDTYPE := { netrand | determ }
VAL := number not exceeding 10000
JUMP_COUNT := absolute jump from start of action list
INDEX := index value used
DESCRIPTION
The gact action allows reclassify, dropping, passing, or accepting pack-
ets. At the moment there are only two algorithms. One is deterministic
and the other uses internal kernel netrand.
OPTIONS
random RANDTYPE CONTROL VAL
The probability of taking the action expressed in terms of 1 out
of VAL packets.
CONTROL
Indicate how tc should proceed if the packet matches. For a de-
scription of the possible CONTROL values, see tc-actions(8).
EXAMPLES
Apply a rule on ingress to drop packets from a given source address.
# tc filter add dev eth0 parent ffff: protocol ip prio 6 u32 match ip src 10.0.0.9/32 flowid 1:16 action drop
Allow 1 out 10 packets from source randomly using the netrand generator
# tc filter add dev eth0 parent ffff: protocol ip prio 6 u32 match ip src 10.0.0.9/32 flowid 1:16 action drop random netrand ok 10
Deterministically accept every second packet
# tc filter add dev eth0 parent ffff: protocol ip prio 6 u32 match ip src 10.0.0.9/32 flowid 1:16 action drop random determ ok 2
SEE ALSO
tc(8), tc-actions(8), tc-u32(8)
iproute2 11 Jan 2023 Generic actions in tc(8)
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