How to upgrade rubygems

Install rubygems-update

gem install rubygems-update
update_rubygems
gem update --system

run this commands as root or use sudo.

You can update all gems by just performing:

sudo gem update

Or:

gem update `gem outdated | cut -d ' ' -f 1`

I found other answers to be inaccurate/outdated. Best is to refer to the actual documentation.

Short version: in most cases gem update --system will suffice.

You should not blindly use sudo. In fact if you're not required to do so you most likely should not use it.

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