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PFLOGD(8)		FreeBSD	System Manager's Manual		     PFLOGD(8)

NAME
     pflogd -- packet filter logging daemon

SYNOPSIS
     pflogd [-DragonFly] [-d delay] [-f	filename] [-s snaplen] [expression]

DESCRIPTION
     pflogd is a background daemon which reads packets logged by pf(4) to the
     packet logging interface pflog0 and writes	the packets to a logfile (nor-
     mally /var/log/pflog) in tcpdump(1) binary	format.	 These logs can	be
     reviewed later using the -r option	of tcpdump(1), hopefully offline in
     case there	are bugs in the	packet parsing code of tcpdump(1).

     pflogd closes and then re-opens the log file when it receives SIGHUP,
     permitting	newsyslog(8) to	rotate logfiles	automatically.	SIGALRM	causes
     pflogd to flush the current logfile buffers to the	disk, thus making the
     most recent logs available.  The buffers are also flushed every delay
     seconds.

     If	the log	file contains data after a restart or a	SIGHUP,	new logs are
     appended to the existing file.  If	the existing log file was created with
     a different snaplen, pflogd temporarily uses the old snaplen to keep the
     log file consistent.

     pflogd tries to preserve the integrity of the log file against I/O
     errors.  Furthermore, integrity of	an existing log	file is	verified
     before appending.	If there is an invalid log file	or an I/O error, log-
     ging is suspended until a SIGHUP or a SIGALRM is received.

     The options are as	follows:

     -D	     Debugging mode.  pflogd does not disassociate from	the control-
	     ling terminal.

     -d	delay
	     Time in seconds to	delay between automatic	flushes	of the file.
	     This may be specified with	a value	between	5 and 3600 seconds.
	     If	not specified, the default is 60 seconds.

     -f	filename
	     Log output	filename.  Default is /var/log/pflog.

     -s	snaplen
	     Analyze at	most the first snaplen bytes of	data from each packet
	     rather than the default of	96.  The default of 96 is adequate for
	     IP, ICMP, TCP, and	UDP headers but	may truncate protocol informa-
	     tion for other protocols.	Other file parsers may desire a	higher
	     snaplen.

     -x	     Check the integrity of an existing	log file, and return.

     expression
	     Selects which packets will	be dumped, using the regular language
	     of	tcpdump(1).

FILES
     /var/run/pflogd.pid  Process ID of	the currently running pflogd.
     /var/log/pflog	  Default log file.

EXAMPLES
     Log specific tcp packets to a different log file with a large snaplen
     (useful with a log-all rule to dump complete sessions):

	   # pflogd -s 1600 -f suspicious.log port 80 and host evilhost

     Display binary logs:

	   # tcpdump -n	-e -ttt	-r /var/log/pflog

     Display the logs in real time (this does not interfere with the operation
     of	pflogd):

	   # tcpdump -n	-e -ttt	-i pflog0

     Tcpdump has been extended to be able to filter on the pfloghdr structure
     defined in	<net/if_pflog.h>.  Tcpdump can restrict	the output to packets
     logged on a specified interface, a	rule number, a reason, a direction, an
     IP	family or an action.

     ip		    Address family equals IPv4.
     ip6	    Address family equals IPv6.
     ifname kue0    Interface name equals "kue0".
     on	kue0	    Interface name equals "kue0".
     rulenum 10	    Rule number	equals 10.
     reason match   Reason equals match.  Also accepts "bad-offset", "frag-
		    ment", "bad-timestamp", "short", "normalize" and "memory".
     action pass    Action equals pass.	 Also accepts "block".
     inbound	    The	direction was inbound.
     outbound	    The	direction was outbound.

     Display the logs in real time of inbound packets that were	blocked	on the
     wi0 interface:

	   # tcpdump -n	-e -ttt	-i pflog0 inbound and action block and on wi0

SEE ALSO
     tcpdump(1), pcap(3), pf(4), pflog(4), pf.conf(5), newsyslog(8)

HISTORY
     The pflogd	command	appeared in OpenBSD 3.0.

AUTHORS
     Can Erkin Acar

FreeBSD	10.1			 July 9, 2001			  FreeBSD 10.1

NAME | SYNOPSIS | DESCRIPTION | FILES | EXAMPLES | SEE ALSO | HISTORY | AUTHORS

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