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Charles-Eric Legras
4,917 PointsLocalhost:3000 - not available
When I launch bin/rails server
I have this message:
[2015-02-16 17:43:38] INFO WEBrick 1.3.1
[2015-02-16 17:43:38] INFO ruby 2.0.0 (2014-05-08) [universal.x86_64-darwin14]
[2015-02-16 17:43:38] WARN TCPServer Error: Address already in use - bind(2)
Exiting
/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/webrick/utils.rb:85:in initialize': Address already in use - bind(2) (Errno::EADDRINUSE)
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/webrick/utils.rb:85:in
new'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/webrick/utils.rb:85:in block in create_listeners'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/webrick/utils.rb:82:in
each'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/webrick/utils.rb:82:in create_listeners'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/webrick/server.rb:132:in
listen'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/webrick/server.rb:113:in initialize'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/webrick/httpserver.rb:45:in
initialize'
from /Library/Ruby/Gems/2.0.0/gems/rack-1.5.2/lib/rack/handler/webrick.rb:11:in new'
from /Library/Ruby/Gems/2.0.0/gems/rack-1.5.2/lib/rack/handler/webrick.rb:11:in
run'
from /Library/Ruby/Gems/2.0.0/gems/rack-1.5.2/lib/rack/server.rb:264:in start'
from /Library/Ruby/Gems/2.0.0/gems/railties-4.0.2/lib/rails/commands/server.rb:84:in
start'
from /Library/Ruby/Gems/2.0.0/gems/railties-4.0.2/lib/rails/commands.rb:76:in block in <top (required)>'
from /Library/Ruby/Gems/2.0.0/gems/railties-4.0.2/lib/rails/commands.rb:71:in
tap'
from /Library/Ruby/Gems/2.0.0/gems/railties-4.0.2/lib/rails/commands.rb:71:in <top (required)>'
from bin/rails:4:in
require'
from bin/rails:4:in `<main>'
I don't understand why, because I worked when I install the testapp...
Please help
3 Answers

Clayton Perszyk
Treehouse Moderator 48,318 PointsHi Charles-Erik
It looks like you're running another app on the same port (localhost:3000). You can only run one app per port, so you'll have to shut down the server for the other app.

Andrew Smith
14,330 PointsThis discussion is a bit old now, but I ran into the same problem today, seemingly out of the blue.
In the OSX console:
lsof -i tcp:3000
Find the port ID (PID) under the resulting listing, then:
kill -9 <PID>
Where PID is the port ID you obtained from running the "lsof" command above. Worked like a charm. Not sure if this syntax would work for Linux or Windows consoles.
I found this solution from Stackoverflow: http://stackoverflow.com/questions/3855127/find-and-kill-process-locking-port-3000-on-mac
Charles-Eric Legras
4,917 PointsThank you Clayton !!! You were right !!! :)
Jennifer Crawshaw
17,878 PointsJennifer Crawshaw
17,878 PointsI am having this issue as well, but I do not have any other apps running on that port, they are all shut down. Any suggestions?