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

# 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

# SEE ALSO

fstat(1), netstat(1)

# HISTORY

The `tcpdrop` program first appeared in OpenBSD 3.6.

# AUTHORS

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

February 6, 2023 | Debian