How to find the process that is using a port
Sometimes when developing multiple applications at once, or trying out demos, I end up with multiple programs running on different ports on my computer: 3000
, 3001
, 1313
, and so on.
If I don’t pay close attention, I might forget which application is running on a specific port.
How can we determine which program is listening on a port?
The lsof
command helps us do that!
Running
lsof -i :1313
Will tell me the command that’s currently listening on port 1313:
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
hugo 8698 fla 4764u IPv4 0xc72ca30d18e45ef9 0t0 TCP localhost:bmc_patroldb (LISTEN)
In this case it’s the hugo
command, with PID 8698.
If I want to terminate that program, I can just run kill 8698
.
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