tc-actions(8) — Linux manual page


actions in tc(8)                    Linux                   actions in tc(8)

NAME         top

       actions - independently defined actions in tc

SYNOPSIS         top

       tc [ TC_OPTIONS ] actions add | change | replace ACTSPEC

       tc [ TC_OPTIONS ] actions get | delete ACTISPEC

       tc [ TC_OPTIONS ] actions flush ACTNAMESPEC

       tc [ TC_OPTIONS ] actions ls | list ACTNAMESPEC [ ACTFILTER ]

               ACTSPEC := action ACTDETAIL [ INDEXSPEC ] [ COOKIESPEC ] [
               FLAGS ] [ HWSTATSSPEC ] [ CONTROL ]


               ACTNAMESPEC := action ACTNAME

               INDEXSPEC := index INDEX

               ACTFILTER := since MSTIME

               COOKIESPEC := cookie COOKIE

               FLAGS := no_percpu

               HWSTATSSPEC := hw_stats { immediate | delayed | disabled }


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

               MSTIME Time since last update.

               CONTROL := { reclassify | pipe | drop | continue | ok }

               TC_OPTIONS These are the options that are specific to tc and
               not only the options. Refer to tc(8) for more information.

DESCRIPTION         top

       The actions object in 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.

OPERATIONS         top

       add    Create a new action in that action's table.

              Make modifications to an existing action.

       get    Display the action with the specified index value. When
              combined with the -s option for tc, display the statistics for
              that action.

       delete Delete the action with the specified index value. If the
              action is already associated with a classifier, it does not
              delete the classifier.

       list   List all the actions in the specified table. When combined
              with the -s option for tc, display the statistics for all
              actions in the specified table.  When combined with the option
              since allows doing a millisecond time-filter since the last
              time an action was used in the datapath.

       flush  Delete all actions stored in the specified table.

ACTION OPTIONS         top

       Note that these options are available to all action types.

       index INDEX
              Specify the table index value of an action.  INDEX is a 32-bit
              value that is unique to the specific type of action

              For add, change, and replace operations, the index is
              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

              For get and delete operations, the index is required to
              identify the specific action to be displayed or deleted.

       cookie COOKIE
              In addition to the specific action, mark the matching packet
              with the value specified by COOKIE.  The 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.

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

       hw_stats HW_STATS
              Specifies the type of HW stats of new action. If omitted, any
              stats counter type is going to be used, according to driver
              and its resources.  The HW_STATS indicates the type. Any of
              the following are valid:

                     Means that in dump, user gets the current HW stats
                     state from the device queried at the dump time.

                     Means that in dump, user gets HW stats that might be
                     out of date for some time, maybe couple of seconds.
                     This is the case when driver polls stats updates
                     periodically or when it gets async stats update from
                     the device.

                     No HW stats are going to be available in dump.

       since MSTIME
              When dumping large number of actions, a millisecond time-
              filter can be specified MSTIME.  The 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.

              The CONTROL indicates how tc should proceed after executing
              the action. Any of the following are valid:

                     Restart the classifiction by jumping back to the first
                     filter attached to the action's parent.

              pipe   Continue with the next action. This is the default

              drop   Drop the packed without running any further actions.

                     Continue the classification with the next filter.

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

SEE ALSO         top

       tc(8), tc-bpf(8), tc-connmark(8), tc-csum(8), tc-ife(8),
       tc-mirred(8), tc-nat(8), tc-pedit(8), tc-police(8), tc-simple(8),
       tc-skbedit(8), tc-skbmod(8), tc-tunnel_key(8), tc-vlan(8), tc-xt(8)

COLOPHON         top

       This page is part of the iproute2 (utilities for controlling TCP/IP
       networking and traffic) project.  Information about the project can
       be found at 
       If you have a bug report for this manual page, send it to,  This page was obtained
       from the project's upstream Git repository
       ⟨⟩ on
       2020-08-13.  (At that time, the date of the most recent commit that
       was found in the repository was 2020-06-24.)  If you discover any
       rendering problems in this HTML version of the page, or you believe
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iproute2                         1 Aug 2017                 actions in tc(8)

Pages that refer to this page: simple(8)tc-simple(8)