>sudo apt-get install ruby
Err http://us.archive.ubuntu.com/ubuntu/ lucid/main ruby 4.2
Something wicked happened resolving 'us.archive.ubuntu.com:http'
(-5 - No address associated with hostname)
Failed to fetch
This error is caused because you have not setup the correct proxy setting in your apt.conf.
To fix this issue simply add the following line into your /etc/apt/apt.conf file as setting up the proxy in the export http_proxy env variable won't solve this issue.
> sudo /etc/apt/apt.conf
Then add the following line into