.TH "actions in tc" 8 "1 Aug 2017" "iproute2" "Linux"

.SH NAME

actions \- independently defined actions in tc

.SH SYNOPSIS

.B tc

[

.I TC_OPTIONS

]

.B actions

.BR add " | " change " | " replace

.I ACTSPEC

.B tc

[

.I TC_OPTIONS

]

.B actions

.BR get " | " delete

.I ACTISPEC

.B tc

[

.I TC_OPTIONS

]

.B actions flush

.I ACTNAMESPEC

.B tc

[

.I TC_OPTIONS

]

.B actions

.BR ls " | " list

.I ACTNAMESPEC

[

.I ACTFILTER

]

.in +8

.I ACTSPEC

:=

.B action

.I ACTDETAIL

[

.I INDEXSPEC

] [

.I COOKIESPEC

] [

.I FLAGS

] [

.I CONTROL

]

.I ACTISPEC

:=

.I ACTNAMESPEC INDEXSPEC

.I ACTNAMESPEC

:=

.B action

ACTNAME

.I INDEXSPEC

:=

.BI index " INDEX"

.I ACTFILTER

:=

.BI since " MSTIME"

.I COOKIESPEC

:=

.BI cookie " COOKIE"

.I FLAGS

:=

.I no_percpu

.I ACTDETAIL

:=

.I ACTNAME ACTPARAMS

.I ACTNAME

may be any valid action type: gact, mirred, bpf, connmark, csum, police, etc.

.I MSTIME

Time since last update.

.I CONTROL

:= {

.IR reclassify " | " pipe " | " drop " | " continue " | " ok

}

.I TC_OPTIONS

These are the options that are specific to

.B tc

and not only the options. Refer to

.BR tc(8)

for more information.

.in

.SH DESCRIPTION

The

.B actions

object in

.B tc

allows a user to define actions independently of a classifier (filter). These

actions can then be assigned to one or more filters, with any

packets matching the classifier's criteria having that action performed

on them.

Each action type (mirred, police, etc.) will have its own table to store

all created actions.

.SH OPERATIONS

.TP

.B add

Create a new action in that action's table.

.TP

.B change

.TQ

.B replace

Make modifications to an existing action.

.TP

.B get

Display the action with the specified index value. When combined with the

.B -s

option for

.BR tc ","

display the statistics for that action.

.TP

.B delete

Delete the action with the specified index value. If the action is already

associated with a classifier, it does not delete the classifier.

.TP

.B ls

.TQ

.B list

List all the actions in the specified table. When combined with the

.B -s

option for

.BR tc ","

display the statistics for all actions in the specified table.

When combined with the option

.B since

allows doing a millisecond time-filter since the last time an

action was used in the datapath.

.TP

.B flush

Delete all actions stored in the specified table.

.SH ACTION OPTIONS

Note that these options are available to all action types.

.TP

.BI index " INDEX"

Specify the table index value of an action.

.I INDEX

is a 32-bit value that is unique to the specific type of action referenced.

.RS

For

.BR add ", " change ", and"

.B replace

operations, the index is

.BR optional.

When adding a new action,

specifying an index value will assign the action to that index unless that

index value has already been assigned. Omitting the index value for an add

operation will cause the kernel to assign a value to the new action.

.RE

.RS

For

.BR get " and " delete

operations, the index is

.B required

to identify the specific action to be displayed or deleted.

.RE

.TP

.BI cookie " COOKIE"

In addition to the specific action, mark the matching packet with the value

specified by

.IR COOKIE "."

The

.I COOKIE

is a 128-bit value that will not be interpreted by the kernel whatsoever.

As such, it can be used as a correlating value for maintaining user state.

The value to be stored is completely arbitrary and does not require a specific

format. It is stored inside the action structure itself.

.TP

.I FLAGS

Action-specific flags. Currently, the only supported flag is

.I no_percpu

which indicates that action is expected to have minimal software data-path

traffic and doesn't need to allocate stat counters with percpu allocator.

This option is intended to be used by hardware-offloaded actions.

.TP

.BI since " MSTIME"

When dumping large number of actions, a millisecond time-filter can be

specified

.IR MSTIME "."

The

.I MSTIME

is a millisecond count since last time a packet hit the action.

As an example specifying "since 20000" implies to dump all actions

that have seen packets in the last 20 seconds. This option is useful

when the kernel has a large number of actions and you are only interested

in recently used actions.

.TP

.I CONTROL

The

.I CONTROL

indicates how

.B tc

should proceed after executing the action. Any of the following are valid:

.RS

.TP

.B reclassify

Restart the classifiction by jumping back to the first filter attached to

the action's parent.

.TP

.B pipe

Continue with the next action. This is the default control.

.TP

.B drop

Drop the packed without running any further actions.

.TP

.B continue

Continue the classification with the next filter.

.TP

.B pass

Return to the calling qdisc for packet processing, and end classification of

this packet.

.RE

.SH SEE ALSO

.BR tc (8),

.BR tc-bpf (8),

.BR tc-connmark (8),

.BR tc-csum (8),

.BR tc-ife (8),

.BR tc-mirred (8),

.BR tc-nat (8),

.BR tc-pedit (8),

.BR tc-police (8),

.BR tc-simple (8),

.BR tc-skbedit (8),

.BR tc-skbmod (8),

.BR tc-tunnel_key (8),

.BR tc-vlan (8),

.BR tc-xt (8)