Can't open http://localhost:3000 - why?

Question

I can't open http://localhost:3000 .

If it's relevant, here is the rail s command:

Jonass-MBP:first Money$ rails s
=> Booting WEBrick
=> Rails 4.2.6 application starting in development on http://localhost:3000
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
[2016-09-16 02:31:51] INFO  WEBrick 1.3.1
[2016-09-16 02:31:51] INFO  ruby 2.3.1 (2016-04-26) [x86_64-darwin15]
[2016-09-16 02:31:51] INFO  WEBrick::HTTPServer#start: pid=8906 port=3000

Answer 1

要使用端口3000杀死所有进程，请运行kill -9 $(lsof -i tcp:3000 -t) 。