sfcapd(1)																 sfcapd(1)

NAME

       sfcapd - sflow capture daemon

SYNOPSIS

       sfcapd [options]

DESCRIPTION

       sfcapd  is  the	sflow capture daemon of the nfdump tools. It reads sflow data from the network and stores it into nfcapd compatible files.
       The output file is automatically rotated and renamed every n minutes - typically 5 min - according the timestamp YYYYMMddhhmm of the inter-
       val e.g. nfcapd.200407110845 contains the data from July 11th 2004 08:45 onward. sfcapd supports sFlow version 4 and 5 datagrams.

       Sflow is an industry standard developed by InMon Corporation.  For more information see http://sflow.org.

OPTIONS

       -p portnum
	  Specifies the port number to listen. Default port is 6343

       -b bindhost
	  Specifies  the hostname/IPv4/IPv6 address to bind for listening. Can be an IP address or a hostname, resolving to an IP address attached
	  to an interface.  Defaults to any available IPv4 interface, if not specified.

       -4 Forces sfcapd to listen on IPv4 addresses only. Can be used together with -b if a hostname has an IPv4 and IPv6 address record.  Depend-
	  ing on the socket implementation -6 also accepts IPv4 data.

       -6 Forces sfcapd to listen on IPv6 addresses only. Can be used together with -b if a hostname has an IPv4 and IPv6 address record.

       -j MulticastGroup
	  Join the specified IPv6 or IPv6 multicast group for listening.

       -R host[/port}
	  Enable  packet  repeater. Send all incoming packets to another host and port.  host is either a valid IPv4/IPv6 address, or a valid sim-
	  bolic hostname, which resolves to a IPv6 or IPv4 address. port may be ommited and defaults to port 6343. Note: Due to IPv4/IPv6 accepted
	  addresses the port separator is '/'.

       -I IdentString ( capital letter i )
	  Specifies  an  ident string, which describes the source e.g. the name of the router. This string is put into the stat record to identify
	  the source. Default is 'none'. This is for compatibility with nfdump 1.5.x and used to specify a single sflow source. See -n

       -l base_directory ( letter ell )
	  Specifies the base directory to store the output files.  If a sub hierarchy is specified with -S the final directory is concatenated	to
	  base_directory/sub_hierarchy. This is for compatibility with nfdump 1.5.x and used to specify a single sflow source. See -n

       -n <Ident,IP,base_directory>
	  Configures an sflow source named Ident and identified by source IP address IP.  The base directory for the flow files is base_directory.
	  If a sub hierarchy is specified with -S the final directory is concatenated to base_directory/sub_hierarchy.	Multiple  netflow  sources
	  can  be  specified. All data is sent to the same port specified by -p.  Note: You must not mix -n option with -I and -l. Use either syn-
	  tax.

       -f <pcap_file>
	  Read sflow packets from a give pcap_file instead of the network. This requires sfcapd to  be	compiled  with	the  pcap  option  and	is
	  intended for debugging only.

       -S <num>
	  Allows  to  specify  an  additional directory sub hierarchy to store the data files. The default is 0, no sub hierarchy, which means the
	  files go directly in the base directory (-l). The base directory (-l) is concatenated with the specified sub hierarchy  format  to  form
	  the final data directory.  The following hierarchies are defined:
	    0 default	  no hierarchy levels
	    1 %Y/%m/%d	  year/month/day
	    2 %Y/%m/%d/%H year/month/day/hour
	    3 %Y/%W/%u	  year/week_of_year/day_of_week
	    4 %Y/%W/%u/%H year/week_of_year/day_of_week/hour
	    5 %Y/%W/%u	  year/week_of_year/day_of_week
	    6 %Y/%W/%u/%H year/week_of_year/day_of_week/hour
	    7 %Y/%j	  year/day-of-year
	    8 %Y/%j/%H	  year/day-of-year/hour
	    9 %Y-%m-%d	  year-month-day
	   10 %Y-%m-%d/%H year-month-day/hour

       -T <extension list>
	  Specifies  the  list of extensions, to be stored in the flow file.  Regardless of the extension list, the following sflow data is stored
	  per record: first, last, fwd status, tcp flags, proto, (src)tos, src port, dst port, src ipaddr, dst ipaddr, in(packets), in(bytes).	In
	  addition sfcapd recognises the extensions as described below.

	  Extensions:
	   sflow extensions:
	    1 input/output interface SNMP numbers.
	    2 src/dst AS numbers.
	    3 src/dst mask, (dst)TOS, direction,
	    4 Next hop IP addr
	    5 BGP next hop IP addr
	    6 src/dst vlan id labels
	   10 in_src/out_dst MAC address
	   By  default	extension 1 and 2 are selected, which provides compatibility with earlier nfdump version.  Extensions can be added/deleted
	   by specifying a ',' separated list of extension ids. Each id may be prepended by an optional sign +/- to add or remove a given id  from
	   the extension list. The string 'all' means all extensions. Extensions 7-9 are not available for sfcapd.
	   Examples:
	   -T all	Enables all possible extensions.
	   -T +3,+4	Adds extensions 3 and 4 to the defaults 1 and 2.
	   -T all,-5,-6 Set all extensions but 5 and 6
	   -T -1,4	Removes default extension 1 and adds extension 4
	   Note: Extensions are shared with the netflow collector nfcapd. Sflow as well as netflow data is stored in the same type of extensions.

       -t interval
	  Specifies the time interval in seconds to rotate files. The default value is 300s ( 5min ).

       -w Align  file  rotation with next n minute ( specified by -t ) interval.  Example: If interval is 5 min, sync at 0,5,10... wall clock min-
	  utes Default: no alignment.

       -x cmd
	  Run command cmd at the end of every interval, when a new file becomes available. The following command expansion is available:
	   %f	Replaced by the file name e.g nfcapd.200407110845 inluding any
		sub hierarchy. ( 2004/07/11/nfcapd.200407110845 )
	   %d	Replaced by the directory where the file is located.
	   %t	Replaced by the time ISO format e.g. 200407110845.
	   %u	Replaced by the UNIX time format.
	   %i	Replaced ident string given by -I

       -e Auto expire files at every cycle. max lifetime and max filesize are defined using nfexpire(1)

       -P pidfile
	  Specify name of pidfile. Default is no pidfile.

       -D Daemon mode: fork to background and detach from terminal.  Nfcapd terminates on signal TERM, INT and HUP.

       -u userid
	  Change to the user userid as soon as possible. Only root is allowed to use this option.

       -g groupid
	  Change to the group groupid as soon as possible. Only root is allowed use this option.

       -B bufflen
	  Specifies the socket input buffer length in bytes. For high volume traffic ( near GB traffic ) it is recommended to set  this  value	as
	  high as possible ( typically > 100k ), otherwise you risk to lose packets. The default is OS ( and kernel )  dependent.

       -E Print  data  records	in  nfdump raw format to stdout. This option is for debugging purpose only, to see how incoming sflow data is pro-
	  cessed and stored.

       -z Compress flows. Use fast LZO1X-1 compression in output file.

       -V Print sfcapd version and exit.

       -h Print help text to stdout with all options and exit.

RETURN VALUE

       Returns 0 on success, or 255 if initialization failed.

LOGGING

       sfcapd logs to syslog with SYSLOG_FACILITY LOG_DAEMON For normal operation level 'warning' should be fine.  More information is reported at
       level 'info' and 'debug'.

       A small statistic about the collected flows, as well as errors are reported at the end of every interval to syslog with level 'info'.

EXAMPLES

       Compatible with old sfcapd 1.5.x:
	      sfcapd -w -D -l /data/spool/router1 -p 6343 -B 128000 -I router1 -x '/path/some_app -r %d/%f'  -P /var/run/sfcapd/sfcapd.router1

       Selectively enabled sender:
	      sfcapd -Tall -w -D -n router1,192.168.1.10,/data/spool/router1 -p 6343 -B 128000 -P /var/run/sfcapd/sfcapd.router1

NOTES

       sfcapd automatically scales the packets and bytes according the sampling rate.

       Even with sflow version 4 and 5 support, not all available sflow elements are stored in the data files. As of this version, sfcpad supports
       the the same shared fields as extensions, as it's netflow companion nfcapd for netflow version v9. See nfcapd(1). More fields will be  sup-
       ported in future.

       The format of the data files is version independent and compatible nfcapd collected data.

       Socket  buffer:	Setting  the  socket buffer size is system dependent.  When starting up, sfcapd returns the number of bytes the buffer was
       actually set. This is done by reading back the buffer size and may differ from what you requested.

SEE ALSO

       nfcapd(1), nfdump(1), nfprofile(1), nfreplay(1)

								    2009-09-09								 sfcapd(1)