TCPDROP(8) BSD System Manager's Manual TCPDROP(8)
tcpdrop - drop a TCP connection
tcpdrop laddr lport faddr fport tcpdrop laddr.lport faddr.fport tcpdrop laddr:lport faddr:fport
The tcpdrop command drops the TCP connection specified by the local ad- dress laddr, port lport and the foreign address faddr, port fport. Ad- dresses and ports can be specified by name or numeric value.
If a connection to httpd(8) is causing congestion on a network link, one can drop the TCP session in charge: # fstat | egrep 'httpd.*internet.*<--' www httpd 21307 3* internet stream tcp \ 0xd1007ca8 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 If lynx(1) is hanging on a connection again (also works for IPv6)... $ netstat -anv | fgrep .80 tcp 0 0 \ 192.168.0.225.25724 193.99.144.85.80 \ ESTABLISHED ... then this, easily copy/pasted, will drop the connection: $ sudo tcpdrop 192.168.0.225.25724 193.99.144.85.80 Do not forget the -v option to netstat(1) because otherwise, the IP ad- dress may be cut off in the middle.
fstat(1), netstat(1) MirBSD #10-current December 1, 2017 1