Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
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
       interface, with programmable rates  and	possibly  delays,  losses  and
       packet  alterations.  nmreplay is designed to run at high speed,	so the
       transmit	schedule 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 nor-
	       mally transmits packets one at a	time, but it  may  use	larger
	       batches,	 up to the value specified with	this option, when run-
	       ning 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 com-
	       puted  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) indicates 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 distri-
	       bution  can  be	constant,  uniform  or exponential.  dt, dmin,
	       dmax, avt are times expressed as	floating point numbers option-
	       ally followed by	a character (s,	m, u, n) to indicate  seconds,
	       milliseconds, microseconds, 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	trans-
	       mission.

OPERATION
       nmreplay	creates	an in-memory schedule with all packets to be transmit-
       ted,  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 14.quarterly     December	21, 2018		   NMREPLAY(8)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=nmreplay&sektion=8&manpath=FreeBSD+Ports+14.3.quarterly>

home | help