Ruby on Rails mac issue with server already running - ruby-on-rails

Question

Im trying to get started learning Ruby on Rails and I'm having an issue getting server to start or stop correctly and I'm not sure why.
As i understand it, when i start a server up it will run until i hit Ctrl + C to shut it down.
However if i run bin/rails server to start it up it says there is already a server running at port 3000 so i need to use a different port, which ive done below. I don't want to keep making new ports each time.
What am i doing wrong folks?
Gavins-MacBook-Pro:buro MacBook$ bin/rails server -p 3001
=> Booting WEBrick
=> Rails 4.2.1 application starting in development on http://localhost:3001
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
A server is already running. Check /Users/MacBook/buro/tmp/pids/server.pid.
Exiting
Gavins-MacBook-Pro:buro MacBook$
Gavins-MacBook-Pro:buro MacBook$ bin/rails server -p 3001
=> Booting WEBrick
=> Rails 4.2.1 application starting in development on http://localhost:3001
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
A server is already running. Check /Users/MacBook/buro/tmp/pids/server.pid.
Exiting
Gavins-MacBook-Pro:buro MacBook$ bin/rails server -p 3002
=> Booting WEBrick
=> Rails 4.2.1 application starting in development on http://localhost:3002
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
A server is already running. Check /Users/MacBook/buro/tmp/pids/server.pid.
Exiting
Gavins-MacBook-Pro:buro MacBook$
Also i tried removing the pid file but then i still get this:
Gavins-MacBook-Pro:buro MacBook$ bin/rails server
=> Booting WEBrick
=> Rails 4.2.1 application starting in development on http://localhost:3000
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
[2015-07-24 10:58:14] INFO WEBrick 1.3.1
[2015-07-24 10:58:14] INFO ruby 2.2.2 (2015-04-13) [x86_64-darwin14]
Exiting
/Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/socket.rb:206:in `bind': Address already in use - bind(2) for 127.0.0.1:3000 (Errno::EADDRINUSE)
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/socket.rb:206:in `listen'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/socket.rb:461:in `block in tcp_server_sockets'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/socket.rb:232:in `each'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/socket.rb:232:in `foreach'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/socket.rb:459:in `tcp_server_sockets'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/webrick/utils.rb:70:in `create_listeners'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/webrick/server.rb:133:in `listen'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/webrick/server.rb:114:in `initialize'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/webrick/httpserver.rb:45:in `initialize'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rack-1.6.4/lib/rack/handler/webrick.rb:31:in `new'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rack-1.6.4/lib/rack/handler/webrick.rb:31:in `run'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rack-1.6.4/lib/rack/server.rb:286:in `start'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/server.rb:80:in `start'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/commands_tasks.rb:80:in `block in server'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/commands_tasks.rb:75:in `tap'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/commands_tasks.rb:75:in `server'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands.rb:17:in `<top (required)>'
from /Users/MacBook/buro/bin/rails:8:in `require'
from /Users/MacBook/buro/bin/rails:8:in `<top (required)>'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/client/rails.rb:28:in `load'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/client/rails.rb:28:in `call'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/client/command.rb:7:in `call'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/client.rb:26:in `run'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/bin/spring:48:in `<top (required)>'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/binstub.rb:11:in `load'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/binstub.rb:11:in `<top (required)>'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
from /Users/MacBook/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
from /Users/MacBook/buro/bin/spring:13:in `<top (required)>'
from bin/rails:3:in `load'
from bin/rails:3:in `<main>'

Answer 1

Do
ps ax | grep server
and look for your rails servers. The first number in each result line is the process id, aka "pid". You can kill these processes like
kill -9 12345
where 12345 is an example pid.
Kill them all and then do
rm tmp/pids/server.pid
for good measure. These are all done in Terminal by the way, in your application's root folder (where you run the server from).