TCPDROP(8) - System Manager’s Manual #

TCPDROP(8) - System Manager’s Manual

NAME #

tcpdrop - drop a TCP connection

SYNOPSIS #

tcpdrop local-addr local-port remote-addr remote-port

DESCRIPTION #

The tcpdrop command drops the TCP connection specified by the local address local-addr, port local-port and the foreign address remote-addr, port remote-port. Addresses and ports can be specified by name or numeric value.

To simplify dropping TCP connections using the output of fstat(1) and netstat(1), tcpdrop also supports a two-argument form where the address and port are separated by a colon (’:’) or dot (’.’) character.

EXAMPLES #

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

$ fstat | grep 'httpd.*internet.*<--'
www      httpd      21307    3* internet stream tcp \
	0xd1007ca8 192.168.5.41:80 <-- 192.168.5.1:26747

Either of the following commands will drop the connection:

# tcpdrop 192.168.5.41 80 192.168.5.1 26747

# tcpdrop 192.168.5.41:80 192.168.5.1:26747

# tcpdrop 192.168.5.41.80 192.168.5.1.26747

HISTORY #

The tcpdrop program first appeared in OpenBSD 3.6.

AUTHORS #

The tcpdrop program was written by Markus Friedl <markus@openbsd.org>.

OpenBSD 7.5 - February 6, 2023