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

NAME
     tcpdrop -- drop TCP connections

SYNOPSIS
     tcpdrop local-address local-port foreign-address foreign-port
     tcpdrop [-l] -a

DESCRIPTION
     The  tcpdrop  command  may be used to drop TCP connections from the command
     line.

     If -a is specified then tcpdrop will attempt to  drop  all  active  connec-
     tions.  The -l flag may be given to list the tcpdrop invocation to drop all
     active connections one at a time.

     If -a is not specified then only the connection between the given local ad-
     dress   local-address,   port   local-port,   and	 the   foreign	 address
     foreign-address, port foreign-port, will be dropped.

     Addresses and ports may be specified by name or numeric value.   Both  IPv4
     and IPv6 address formats are supported.

     The  addresses  and  ports may be separated by periods or colons instead of
     spaces.

EXIT STATUS
     The tcpdrop utility exits 0 on success, and >0 if an error occurs.

EXAMPLES
     If a connection to httpd(8) is causing congestion on a  network  link,  one
     can drop the TCP session in charge:

	   # sockstat -c | grep httpd
	   www	    httpd      16525 3	tcp4 \
		   192.168.5.41:80	192.168.5.1:26747

     The following command will drop the connection:

	   # tcpdrop 192.168.5.41 80 192.168.5.1 26747

     The  following  command will drop all connections but those to or from port
     22, the port used by sshd(8):

	   # tcpdrop -l -a | grep -vw 22 | sh

SEE ALSO
     netstat(1), sockstat(1)

AUTHORS
     Markus Friedl <markus@openbsd.org>
     Juli Mallett <jmallett@FreeBSD.org>

FreeBSD 8.4-stable		January 30, 2013		      TCPDROP(8)
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