This problem was truly maddening. Some kind of rogue tcp process spawned by mongrel was not getting closed properly.
It was truly a ghost in the machine.
Doing a ‘ps aux | grep ruby’ or ‘ps aux | grep 3000’ yielded nothing. So it was darn neigh impossible to find a process to kill that was somehow still holding onto the socket. Attempting to start mongrel yielded the “Address already in use – bind(2) (Errno::EADDRINUSE)” error.
This link provided the answer.
If you normally run your mongrel(s) on port 3000, use the following snippet to kill em dead:
kill -HUP `lsof -t -i TCP:3000`
The following is the complete stack trace:
** Ruby version is not up-to-date; loading cgi_multipart_eof_fix
=> Booting Mongrel (use 'script/server webrick' to force WEBrick)
=> Rails application starting on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
** Starting Mongrel listening at 0.0.0.0:3000
Exiting
/usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/lib/mongrel/tcphack.rb:12:in `initialize_without_backlog': Address already in use - bind(2) (Errno::EADDRINUSE)
from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/lib/mongrel/tcphack.rb:12:in `initialize'
from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/lib/mongrel.rb:92:in `initialize'
from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/lib/mongrel/configurator.rb:139:in `listener'
from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/mongrel_rails:99:in `cloaker_'
from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/lib/mongrel/configurator.rb:50:in `initialize'
from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/mongrel_rails:84:in `run'
from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/lib/mongrel/command.rb:212:in `run'
from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/mongrel_rails:281
... 6 levels...
Good luck!
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hi thanks for that