Upgrading from Rails 4.2.1

Question

I am working on upgrading my Rails app.

My rails app's current Rails version is 4.2.1 and Ruby version is 2.3.6.

I have the below questions:

1. What is the stable version of Rails?
2. To which Rails version is it recommended to upgrade from 4.2.1?
3. Is it recommended to upgrade Ruby version along with Rails version?

Thanks in advance

Answer 1

1. At the time of writing - stable is 5.2.3, but 6.0.0.rc1 is production ready. You can look up versions at rubygems
2. It's better to upgrade one minor version at a time from the latest patch - at each step ensure that you have fixed all deprecations and everything is working (tests pass etc.). Most significant changes are described in upgrade guide
3. Ruby upgrade is a separate step, better is to upgrade ruby prior to rails

So in your case i'd do:

4.2.1 -> 4.2.11.1 -> 5.0.7.2 -> 5.1.7 -> 5.2.3 -> ruby 2.4 -> ruby 2.5 -> ruby 2.6 -> 6.0.0.rc1