3
1
In OSX if I type netstat I can see certain things that have an established connection. I don't want to change any settings to close these, I just want to be able to close whatever I ports I choose in the terminal. How do you do that?
3
1
In OSX if I type netstat I can see certain things that have an established connection. I don't want to change any settings to close these, I just want to be able to close whatever I ports I choose in the terminal. How do you do that?
6
You can't close an open socket just like this. Ideally, you would just kill the process that has established the connection.
Check your connections with lsof
(netstat
won't show the process), filtering the output with whatever connection status you want:
lsof -i
lsof -i | grep LISTEN
lsof -i | grep ESTABLISHED
Or, to get the port, e.g. 17500
:
lsof -i:17500
Then, just kill the process. For example:
$ lsof -i | grep "Skype"
Skype 438 werner 9u IPv4 0xffffff801dd0c640 0t0 UDP localhost:52218
Skype 438 werner 42u IPv4 0xffffff80231a7a08 0t0 TCP *:29429 (LISTEN)
Skype 438 werner 43u IPv4 0xffffff8022e18a40 0t0 UDP *:29429
Kill Skype:
killall Skype
Note though that this won't prevent the connections from being made – something you have to specify in your Firewall preferences.
3
Can also use the use the fuser
or netstat
commands.
fuser
syntax is
fuser -k -n protocol portno
Example:
$ fuser -k -n udp 7777
7777/udp: 11774
The number 11774 is the pid.
netstat
example:
$ sudo netstat -ap | grep :9050
tcp 0 0 localhost:9050 *:* LISTEN 1613/tor
The number 1613 is the pid and "tor" is the process name.
Once you have the pid just end it using the kill or killall command
kill pid
or
killall -9 command_name
Still doesn't answer how to close a port. But rather kill the process that created/opened it. What if a process holds >1 open port. How could I kill one but not the other – Michael W – 2016-10-06T10:37:40.923
Your instructions are for showing the perceived symptoms described in the question, open ports belonging to processes. You left out how to accomplish the desired task, to close the port. – Eroen – 2012-09-15T10:20:21.840
1Do you want to close extant connections, prevent further ones on the same port, or both? – Darael – 2012-04-03T13:18:17.807