出错日志：

[ 2015-03-18 08:20:34.2685 30377/7f38a31bd700 App/Implementation.cpp:287 ]: Could not spawn process for application /home/xyt/web/web/root/myread: An error occurred while starting up the preloader. It exited before signalling successful startup back to Phusion Passenger.
  Error ID: c1229380
  Error details saved to: /tmp/passenger-error-gDSnCw.html
  Message from application: An error occurred while starting up the preloader. It exited before signalling successful startup back to Phusion Passenger. Please read <a href="https://github.com/phusion/passenger/wiki/Debugging-application-startup-problems">this article</a> for more information about this problem.<br>
<h2>Raw process output:</h2>
<pre>
*** ERROR ***: Cannot execute /root/.rbenv/shims/ruby: Permission denied (13)
</pre>

[ 2015-03-18 08:20:34.2749 30377/7f389c8ef700 age/Hel/Req/CheckoutSession.cpp:252 ]: [Client 1-1] Cannot checkout session because a spawning error occurred. The identifier of the error is c1229380. Please see earlier logs for details about the error.
^Croot@linshuizhaoying:/home/xyt# sudo tail -f /tmp/passenger-error-gDSnCw.html
                        <div class="container">
                                Powered by <a href="https://www.phusionpassenger.com/">Phusion Passenger</a>,
                                <tt>mod_rails</tt> / <tt>mod_rack</tt> for Apache and Nginx.


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google 了半天没有解决办法，希望以前遇到过这类问题的大牛能给个方案。