Unable to install Rails. Getting Error message.

Question

Ubuntu is such a pain sometimes. I am trying to install a specific version of rails (4.2.2) for the Rails tutorial I am doing and my commandline is screaming this code at me in response. Could someone point me in the right direction? Thank you.

I first put...

sudo gem install rails -v 4.2.2

and then I get this big ugly thing...

Building native extensions.  This could take a while...
ERROR:  Error installing rails:
ERROR: Failed to build gem native extension.

/usr/bin/ruby1.9.1 extconf.rb
/usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file -- mkmf (LoadError)
from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
from extconf.rb:1:in `<main>'


Gem files will remain installed in /var/lib/gems/1.9.1/gems/json-1.8.3 for inspection.
Results logged to /var/lib/gems/1.9.1/gems/json-1.8.3/ext/json/ext/generator/gem_make.out

score 1 · Answer 1 · answered Jul 16 '15 at 22:32

1

You may want to update your RubyGems because Rails 4.2 requires the latest version of RubyGems. Run gem update --system to get the latest dependencies and then gem install rails -v 4.2.2 and the error should go away.

answered Jul 16 '15 at 22:32

Rod Argumedo

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It says that Debian doesn't support that command because it could possibly break my computer. Any ideas? – Erik Aasland Jul 16 '15 at 22:38
What Ruby version you have? – Rod Argumedo Jul 16 '15 at 22:47
Another point to mention, use @tompave's answer to get [RVM](http://rvm.io) and install Ruby 2.2.2 or your version of preference. – Rod Argumedo Jul 16 '15 at 22:53
Below the vote up/down buttons, there is a check button and click it to award the user for the most helpful answer. – Rod Argumedo Jul 16 '15 at 23:11

score 1 · Accepted Answer · edited May 23 '17 at 11:58

1

You might want to look at this question.

Also, you seem to be using a default system ruby installed via apt-get. Consider using rvm instead, as it automatically takes care of installing missing dependencies via your package manager.

edited May 23 '17 at 11:58

Community

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answered Jul 16 '15 at 22:32

tompave

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Unable to install Rails. Getting Error message.

2 Answers2