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

NAME
       fprobe -	a NetFlow probe

SYNOPSIS
       fprobe [options]	remote:port[/[local][/type]] ...

DESCRIPTION
       fprobe  - libpcap-based tool that collect network traffic data and emit
       it as NetFlow flows towards the specified collector.

OPTIONS
       -h     Display short help

       -p     Don't put	the interface into promiscuous mode.  Note  that  even
	      if  this	option	is used, the interface might be	in promiscuous
	      mode for some other reason.

       -i _interface_
	      Listen on	interface. If unspecified, fprobe will use  result  of
	      pcap_lookupdev()	function.  On  Linux systems with 2.2 or later
	      kernels, an interface argument of	`any' can be used  to  capture
	      packets from all interfaces. Note	that captures on the `any' de-
	      vice will	not be done in promiscuous mode.
	      You may use `-' as interface name	to process files  produced  by
	      tcpdump with -w flag. fprobe will	read data from stdin.

       -f _expression_
	      Filter  expression selects which packets will be captured. If no
	      expression is given, all packets on the net  will	 be  captured.
	      Otherwise,  only	packets	for which expression is	`true' will be
	      captured.
	      fprobe use silly IP-packet detection method, so it is  bad  idea
	      to  leave	 the filter empty. For general use `ip'	(-fip) is good
	      filter expression.
	      Read tcpdump manual for detailed expression syntax.

       -s _seconds_
	      How often	scan for expired flows.	[default=5]

       -g _seconds_
	      Fragmented flow lifetime.	[default=30]

       -d _seconds_
	      Idle flow	lifetime (inactive timer). [default=60]

       -e _seconds_
	      Active flow lifetime (active timer). [default=300]

       -n _version_
	      NetFlow version for use (1, 5, 7). [default=5]

       -a _address_
	      Use address as source for	NetFlow	flow.

       -x _inputID_[:_outputID_]
	      Workaround for SNMP interfaces indexes. [default=0]
	      The second parameter may be omitted - in	this  case  its	 value
	      will be equal to the first.
	      See BUGS section.

       -b _flows_
	      Memory bulk size.	[default=200 or	10000]
	      Note  that  maximum  and default values depends on compiling op-
	      tions (--with-membulk parameter).

       -m _kilobytes_
	      Memory limit for flows cache (0=no limit). [default=0]

       -q _flows_
	      Pending queue length. [default=100]
	      Each captured packet at first puts into  special	buffer	called
	      `pending	queue'.	 Purpose  of  this  buffer is to separate most
	      time-critical packet capture thread from other.

       -B _kilobytes_
	      Kernel capture buffer size (0=don't change). [default=0]
	      Increase kernel capture buffer size is most adequate way to pre-
	      vent  packets  loss.  Unfortunately,  at	present	 there	is  no
	      straight way to set the buffer size throught  libpcap,  so  this
	      option  is  a  hack. Moreover, now this hack take	effect only on
	      socket()-based capture mechanisms: it mean that it work on Linux
	      and don't	work on	BSD systems with their bpf().
	      Note  that  maximum  allowed size	of the buffer in Linux limited
	      and generally relatively small, so it should need	to change  the
	      maximum: sysctl -w net/core/rmem_max=4194304

       -r _priority_
	      Real-time	priority (0=disabled). [default=0]
	      If  parameter greater then zero fprobe will use real-time	sched-
	      uling policy to prevent packets loss. Note that possible	values
	      for this option depends on operating system.

       -t _B:N_
	      Emitting rate limit (0:0=no limit). [default=0:0]
	      Produce  N nanosecond delay after	each B bytes sent. This	option
	      may be useful with slow interfaces  and  slow  collectors.  Note
	      that  the	 suspension  time may be longer	than requested because
	      the argument value is rounded up to an integer multiple  of  the
	      sleep  resolution	 (it depends on	operating system and hardware)
	      or because of the	scheduling of other activity by	the system.
	      See BUGS section.

       -S _bytes_
	      Snaplen (0=whole packet).	[default=256]
	      Number of	bytes to capture from packet on	wire.

       -K _bytes_
	      Link layer header	size. By default fprobe	take this  information
	      from  libpcap,  but  sometimes  obtained size unsuitable for our
	      purpose. It occurs, for example, on trunk	interfaces in VLAN en-
	      viroment,	 where	link  layer  header  contain  additional  VLAN
	      header.
	      See EXAMPLES section.

       -k     Don't exclude link layer header from  packet  size.  By  default
	      fprobe counts only IP-part of packet.

       -c _directory_
	      Directory	to chroot to.

       -u _user_
	      User to run as.

       -v _level_
	      Maximum  displayed  log level. (0=EMERG, 1=ALERT,	2=CRIT,	3=ERR,
	      4=WARNING, 5=NOTICE, 6=INFO, 7=DEBUG) [default=6]

       -l _[dst][:id]_
	      Log  destination	(0=none,  1=syslog,  2=stdout,	 3=both)   and
	      log/pidfile identifier. [default=1]
	      This  option  allows  to	select	opportune  log destination and
	      process identifier. The identifier helps to distinguish  pidfile
	      and logs of one fprobe process from other.
	      Note  that  if  log destination contains `stdout'	(equal 2 or 3)
	      fprobe will run in foreground.

       remote:port/local/type
	      Parameters remote	and port are respectively define  address  and
	      port of the NetFlow collector.
	      The local	parameter allows binding certain local IP address with
	      specified	collector. If the parameter is omitted the  value  (if
	      any) of -a option	will be	used.
	      The  type	 parameter determines emitting behavior. It may	be `m'
	      for mirroring (by	default) and `r'  for  collectors  round-robin
	      rotating.
	      You may specify multiple collectors.

EXAMPLES
       Web traffic trivial capturing:
       fprobe -ippp0 -f"tcp&&port 80" localhost:2055

       Capturing from trunk interface:
       fprobe -ieth0 -f"vlan&&ip" -K18 localhost:2055

       Reasonable configuration	to run under heavy load:
       fprobe -fip -B4096 -r2 -q10000 -t10000:10000000 localhost:2055

       Send  packets to	collector at 10.1.1.1:2055 and distribute them between
       collectors at 10.1.1.2:2055 and at 10.1.1.3:2055	on a  round-robin  ba-
       sis:
       fprobe 10.1.1.1:2055 10.1.1.2:2055//r 10.1.1.3:2055//r

BUGS
       SNMP interfaces indexes and packet direction.
       Unfortunately  libpcap  don't  provide  any routing-related information
       about captured packet, therefore	there are no straight ways  to	deter-
       mine  and distinguish input and output interfaces. However -x option at
       least can tell that flow	was passed through the certain interface. Also
       you may launch several instances	of the program with tricky set of fil-
       ters to mark out	each possible packet direction:
       fprobe -x1:2 -ieth1 -f"ip&&dst net 10.2"	localhost:2055
       fprobe -x2:1 -ieth2 -f"ip&&dst net 10.1"	localhost:2055

       Slow interfaces and slow	collectors.
       There are may be	problems with slow interfaces and slow collectors.  It
       effects	as  emitted  packets loss. On the one hand silent non-blocking
       sendto()	implementation can't guarantee that packet was really sent  to
       collector - it may be dropped by	kernel due to outgoing buffer shortage
       (slow interface's problem) and on the other hand	packet may be  dropped
       on  collector's machine due the similar reason -	incoming buffer	short-
       age (slow collector's problem).
       Use -t option as	workaround for this issue.

SEE ALSO
       tcpdump pcap(3)
       http://www.cisco.com/go/netflow

fprobe 1.1			  2005-01-29			     fprobe(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | BUGS | SEE ALSO

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