NAME

       gate - Stream Gate Action

SYNOPSIS

       tc  ...  action gate
               [ base-time BASETIME ] [ clockid CLOCKID ]
               sched-entry <gate state> <interval 1> [ <internal priority> <max octets> ]
               sched-entry <gate state> <interval 2> [ <internal priority> <max octets> ]
               sched-entry <gate state> <interval 3> [ <internal priority> <max octets> ]
               ......
               sched-entry <gate state> <interval N> [ <internal priority> <max octets> ]

DESCRIPTION

       GATE  action  allows  specified  ingress  frames  can  be  passed at specific time slot, or be dropped at
       specific time slot. Tc filter filters the ingress frames, then tc gate action would  specify  which  time
       slot and how many bytes these frames can be passed to device and which time slot frames would be dropped.
       Gate  action  also assign a base-time to tell when the entry list start.  Then gate action would start to
       repeat the gate entry list cyclically at the start base-time.  For the software simulation,  gate  action
       requires the user assign reference time clock type.

PARAMETERS

       base-time
              Specifies  the  instant in nanoseconds, defining the time when the schedule starts. If 'base-time'
              is a time in the past, the schedule will start at

              base-time + (N * cycle-time)

              where N is the smallest integer so the resulting time is greater than "now", and  "cycle-time"  is
              the  sum  of  all  the intervals of the entries in the schedule. Without base-time specified, will
              default to be 0.

       clockid
              Specifies the clock to be used by qdisc's internal timer for measuring time and scheduling events.
              Not valid if gate action is used for offloading filter.   For  example,  tc  filter  command  with
              skip_sw parameter.

       sched-entry
              There may multiple sched-entry parameters in a single schedule. Each one has the format:

              sched-entry <gate state> <interval> [ <internal priority> <max octets> ]

              <gate state> means gate states. 'open' keep gate open, 'close' keep gate close.
              <interval> means how much nano seconds for this time slot.
              <internal  priority>  means  internal  priority value. Present of the internal receiving queue for
              this stream. "-1" means wildcard.  <internal priority> and <max octets> can be omit default to  be
              "-1" which both
               value to be "-1" for this <sched-entry>.
              <max octets> means how many octets size could pass in this time slot. Dropped if overlimited. "-1"
              means  wildcard.  <max  octets>  can  be  omit  default to be "-1" which value to be "-1" for this
              <sched-entry>.
              Note that <internal priority> and <max octets> are nothing meaning for gate state is "close" in  a
              "sched-entry". All frames are dropped when "sched-entry" with "close" state.

EXAMPLES

       The  following example shows tc filter frames source ip match to the 192.168.0.20 will keep the gate open
       for 200ms and limit the traffic to 8MB in this sched-entry. Then keep the traffic gate to  be  close  for
       100ms.   Frames  arrived  at gate close state would be dropped. Then the cycle would run the gate entries
       periodically. The schedule will start at instant 200.0s using the reference CLOCK_TAI.  The  schedule  is
       composed of two entries each of 300ms duration.

       # tc qdisc add dev eth0 ingress
       # tc filter add dev eth0 parent ffff: protocol ip \
                  flower skip_hw src_ip 192.168.0.20 \
                  action gate index 2 clockid CLOCK_TAI \
                  base-time 200000000000ns \
                  sched-entry open 200000000ns -1 8000000b \
                  sched-entry close 100000000ns

       Following commands is an example to filter a stream source mac match to the 10:00:80:00:00:00 icmp frames
       will  be  dropped  at  any  time with cycle 200ms.  With a default basetime 0 and clockid is CLOCK_TAI as
       default.

       # tc qdisc add dev eth0 ingress
       # tc filter add dev eth0 parent ffff:  protocol ip \
            flower ip_proto icmp dst_mac 10:00:80:00:00:00 \
            action gate index 12 sched-entry close 200000000ns

AUTHORS

       Po Liu <Po.Liu@nxp.com>

iproute2                                           12 Mar 2020                                           GATE(8)