Bundler 2.0.1 installed, Rails says “must use Bundler 2 or greater”?

Question

I\'m a Rails newb who\'s trying out Rails on a DigitalOcean droplet. The installations seemed to work fine, but I\'m getting a curious error message when I try to generate a

Answer 1

I got issue after updating ruby version(2.4.6) as-

You must use Bundler 2 or greater with this lockfile.

Here is how I resolved it-
When i checked bundler version bundler -v

$ Bundler version 1.16.1  

I updated bundlere version using-

$ gem install bundler -v 2.0.1

And got issue resolved!

Answer 2

I ran into the same issue & resolved it by downgrading with gem uninstall bundler, followed by gem install bundler -v 1.17.3 to revert back to the last pre 2 version.

I saw this across 3 separate systems using different version managers (ASDF, rbenv, rvm) and this resolved the issue.

There is some information on getting both versions to play nicely here. The root cause of this issue may have been a bug (which appears to have since been fixed)

Per the comment from @MatijsvanZuijlen below, and the bundler documentation, you should also be able to specify which version of bundler you want to use at runtime with bundle _1.17.3_ install

Answer 3

This helped me: gem update --system

Answer 4

This is my solution:

1. (if you have an old version of Bundler), run the command:

   bundle update --bundler

2. Run the command:

   gem update --system

3. run the rake

   rake db:migrate

Answer 5

After you try any of the solutions above, restart your terminal window.

I was stuck with my terminal showing 2 versions of bundler even when i uninstalled the old version until i killed terminal and opened a new window.