Rubygems permission problem when using sudo - ruby

Question

I use sudo to install gems and update rubygems itself but this causes the problem of all new files in /usr/lib/ruby/gems/1.8/gems to be owned by root:root with a permission of 750
This in turn causes most gems to fail to load.
For example, I recently updated rubygems and if I try gem env I get:
/usr/local/lib/site_ruby/1.8/rubygems/specification.rb:512:in `read': Permission denied - /usr/lib/ruby/gems/1.8/specifications/rubygems-update-1.6.2.gemspec (Errno::EACCES)
from /usr/local/lib/site_ruby/1.8/rubygems/specification.rb:512:in `load'
from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:116:in `load_gems_in'
from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:115:in `each'
from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:115:in `load_gems_in'
from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:112:in `reverse_each'
from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:112:in `load_gems_in'
from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:309:in `refresh!'
from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:67:in `from_gems_in'
from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:47:in `from_installed_gems'
from /usr/local/lib/site_ruby/1.8/rubygems.rb:1025:in `source_index'
from /usr/local/lib/site_ruby/1.8/rubygems/gem_path_searcher.rb:135:in `init_gemspecs'
from /usr/local/lib/site_ruby/1.8/rubygems/gem_path_searcher.rb:14:in `initialize'
from /usr/local/lib/site_ruby/1.8/rubygems.rb:984:in `new'
from /usr/local/lib/site_ruby/1.8/rubygems.rb:984:in `searcher'
from /usr/local/lib/site_ruby/1.8/rubygems.rb:206:in `try_activate'
from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:57:in `require'
from /usr/local/lib/site_ruby/1.8/rubygems/config_file.rb:55
from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:36:in `gem_original_require'
from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
from /usr/local/lib/site_ruby/1.8/rubygems/gem_runner.rb:8
from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:36:in `gem_original_require'
from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
from /usr/bin/gem:9
The current workaround is to chmod all files to be readable by everyone but this is getting really annoying.
Some server stats:
uname -a gives
Linux HomeBox 2.6.35 28-server #49-Ubuntu SMP Tue Mar 1 14:55:37 UTC 2011 x86_64 GNU/Linux
sudo gem env gives
RubyGems Environment:
- RUBYGEMS VERSION: 1.6.2
- RUBY VERSION: 1.8.7 (2010-06-23 patchlevel 299) [x86_64-linux]
- INSTALLATION DIRECTORY: /usr/lib/ruby/gems/1.8
- RUBY EXECUTABLE: /usr/bin/ruby1.8
- EXECUTABLE DIRECTORY: /usr/bin
- RUBYGEMS PLATFORMS:
- ruby
- x86_64-linux
- GEM PATHS:
- /usr/lib/ruby/gems/1.8
- /home/nicklas/.gem/ruby/1.8
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :benchmark => false
- :backtrace => false
- :bulk_threshold => 1000
- REMOTE SOURCES:
- http://rubygems.org/
ruby -v gives
ruby 1.8.7 (2010-06-23 patchlevel 299) [x86_64-linux]
I'd be happy to provide more info on the problem.
Update
I just cleaned out all ruby and rubygems stuff and reinstalled it. Same problem.

Answer 1

I use Ubuntu at home too, and after many problems with using apt to install, I discovered RVM.
RVM is super-simple to install, and gets you up and running quickly and easily. But once you start using it for a while, you'll discover that it is superior to any OS package system because it has features that allow you to:
Install multiple versions of Ruby and JRuby and easily switch between them. I can just issue rvm use 1.9.2 or rvm use jruby-1.6.2 and my path is switched automatically and everthing just works.
Install sets of gems into "gemsets" which allow you to use the same gems across multiple ruby versions, so you don't have to manually reinstall. Also, you can switch between gemsets so you can isolate experimental gem versions, etc.
My recommendation is to uninstall the native ruby package, and install RVM. You'll be glad you did.