tell if a port is in use

netstat -a --numeric-ports | grep 8321
if you don't do --numeric-ports, netstat will try to resolve them to names
Sample Output
tcp        0      0 localhost.localdomain:8321  *:*                         LISTEN
tcp        0      0 ::1:8321                    *:*                         LISTEN

1
By: peter4512
2012-01-20 22:00:56

What Others Think

You also can use the short version of --numeric-ports: netstat -an | grep 8321
thomasba · 348 weeks and 3 days ago
You can also use the -p flag to see what process has the port open: netstat -anp | grep port-number
dmmst19 · 348 weeks and 3 days ago
You also can use the short version of --numeric-ports: netstat -an | grep 8321
peribean · 89 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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