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NMREPLAY(8)		     System Manager's Manual		     NMREPLAY(8)

NAME
     nmreplay -- playback a pcap file through a netmap interface

SYNOPSIS
     nmreplay  [-f pcap-file] [-i netmap-interface] [-B bandwidth] [-D delay]
	       [-L loss] [-b batch size] [-w wait-link] [-v] [-C cpu-placement]

DESCRIPTION
     nmreplay works like tcpreplay to replay a pcap file through a netmap inter-
     face, with programmable rates and possibly delays, losses and packet alter-
     ations.   nmreplay is designed to run at high speed, so the transmit sched-
     ule is computed ahead of time, and the thread  in	charge	of  transmission
     only  has	to pump data through the interface.  nmreplay can connect to any
     type of netmap port.

     Command line options are as follows

     -f pcap-file
	     Name of the pcap file to replay.

     -i interface
	     Name of the netmap interface to use as output.  See  netmap(4)  for
	     interface name format.

     -v      Enable verbose mode

     -b batch-size
	     Maximum  batch size to use during transmissions.  nmreplay normally
	     transmits packets one at a time, but it may use larger batches,  up
	     to  the  value  specified	with  this  option, when running at high
	     rates.

     -B bps | constant,bps | ether,bps | real[,speedup]
	     Bandwidth to be used for transmission.  bps  is  a  floating  point
	     number  optionally  follow  by  a character (k, K, m, M, g, G) that
	     multiplies the value by 10^3, 10^6 and 10^9 respectively.	constant
	     (can be omitted) means that the bandwidth	will  be  computed  with
	     reference	to  the  actual packet size (excluding CRC and framing).
	     ether indicates that the ethernet framing (160 bits)  and	CRC  (32
	     bits) will be included in the computation of the packet size.  real
	     means  transmission will occur according to the timestamps recorded
	     in the trace.  The optional speedup multiplier (defaults to 1)  in-
	     dicates  how  much faster or slower than real time the trace should
	     be replayed.

     -D dt | constant,dt | uniform,dmin,dmax | exp, dmin,davg
	     Adds additional delay to the packet transmission,	whose  distribu-
	     tion  can be constant, uniform or exponential.  dt, dmin, dmax, avt
	     are times expressed as floating point numbers  optionally	followed
	     by  a character (s, m, u, n) to indicate seconds, milliseconds, mi-
	     croseconds, nanoseconds.  The delay is added to the  transmit  time
	     and adjusted so that there is never packet reordering.

     -L x | plr,x | ber,x
	     Simulates	packet	or  bit  errors, causing offending packets to be
	     dropped.  x is a floating point number indicating the packet or bit
	     error rate.

     -w wait-link
	     indicates the number of seconds to wait  before  transmitting.   It
	     defaults  to 2, and may be useful when talking to physical ports to
	     let link negotiation complete before starting transmission.

OPERATION
     nmreplay creates an in-memory schedule with all packets to be  transmitted,
     and then launches a separate thread to take care of transmissions while the
     main thread reports statistics every second.

SEE ALSO
     netmap(4)

AUTHORS
     nmreplay  has been written by Luigi Rizzo, Andrea Beconcini, Francesco Mola
     and Lorenzo Biagini at the Universita` di Pisa, Italy.

FreeBSD ports 15.quarterly	December 21, 2018		     NMREPLAY(8)

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<https://man.freebsd.org/cgi/man.cgi?query=nmreplay&sektion=8&manpath=FreeBSD+Ports+15.1.quarterly>

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