Cannot use RVM-installed Ruby with sudo

I have succefully configured RVM to use Ruby 1.9.2 and everything is fine. However when I'm trying to run Ruby using sudo it says it cannot find RVM or Ruby:

$ ruby -v
ruby 1.9.2p0 (2010-开发者_如何转开发08-18 revision 29036) [x86_64-linux]

$ sudo ruby -v
[sudo] password for administrator:
sudo: ruby: command not found

Is that correct behavior or is my RVM misconfigured? Perhaps I should be using the system wide install?

Use rvmsudo command instead of sudo

Taking @calas' answer one step further, add this to your ~/.bashrc:

alias sudo=rvmsudo

This avoids the requirement of having to remember to change sudo to rvmsudo for every command (particularly annoying for copy/pasted commands).

Sudo is resetting your PATH. rvm works by modifying your PATH environment variable so that the ruby you're using is a particular one, probably in your ~/.rvm/rubies directory. When you ruby ruby with sudo, sudo is not using that modified PATH, and so it will not find your rvm ruby. See this question for workarounds: sudo changes PATH - why?

@calas's answer is the answer. but If you can't achieve your goal by using rvmsudo, e.g. install the nginx using the command passenger-install-nginx-module, please just change the owner of the related folder/path. e.g.

$ chown <your_username>:<your_group> /opt -R
$ passenger-install-nginx-module