**We have compiled several types of solutions when you get the following when trying to start the server! It can be solved by either (should).
❯ rails s => Booting Puma => Rails 126.96.36.199 application starting in development on http://localhost:3000 => Run `rails server -h` for more startup options A server is already running. Check project name /tmp/pids/server.pid. Exiting
There are many types, so if you’re having trouble, we recommend that you try them in order.
Occasionally, there are ``server startup status on Mac standard terminal
& trying to start server on a text editor terminal such as VSCode`.
First, check if you are already running the server in another terminal**!
$ rails s => Booting Puma => Rails 188.8.131.52 application starting in development on http://localhost:3000 => Run `rails server -h` for more startup options A server is already running. Check project name /tmp/pids/server.pid. Exiting $ ps aux | grep rails user 28321 s001 S+ 0:00.00 grep rails $ kill -9 28321 $ rails s → resolution
process with port number 3000
$ lsof -wni tcp:3000 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME ruby 28295 user 21u IPv4 0x77d8a30cabb79cc9 0t0 TCP 127.0.0.1:hbci (LISTEN) ruby 28295 user 22u IPv6 0x77d8a30cac93f9f9 0t0 TCP [::1]:hbci (LISTEN) # Copy the PID of the line that says "ruby" in "COMMAND" and stop processing (this time 28295) $ kill -9 28295 $ rails s → resolution
ID used when starting the server
$ rm /tmp/pids/server.pid $ rails s → resolution
The location of this file is in
[app name]/tmp/pids/server.pid, so specify the path and delete it.
Originally, when you quit the server, this file is deleted, but it seems that there is a possibility that it remains an error.
server.pid is created or deleted by starting and stopping the server, you don’t have to worry about it.
kill -9 ○○ that appears frequently is one of the
Linux commands, and is for killing processes.
Personally, I feel that Pattern ② can often end the process easily.
If you stop by starting the server, it will be withered, so please solve it quickly!