This post would demo how to solve the “ruby command not found” after installing the ruby using rbenv, eg. When you input this command to install ruby:

rbenv install --verbose 2.5.1

After install successfully , you input :

ruby -v

You got this:

-bash: ruby: command not found

ok, let’s begin to solve this.


  • rbenv 1.1.1-30-gc8ba27f with plugin ‘ruby-build’ installed
  • ruby 2.5.1 installed by rbenv
  • OS CentOS 6.8


    Before knowing how to solve this problem, let’s check it first by using the rbenv doctor:

curl -fsSL | bash

You got this:

Checking for `rbenv' in PATH: /root/.rbenv/bin/rbenv
Checking for rbenv shims in PATH: not found
  The directory `/root/.rbenv/shims' must be present in PATH for rbenv to work.
  Please run `rbenv init' and follow the instructions.
Checking `rbenv install' support: which: no rbenv-install in (/root/.rbenv/bin:/usr/lib/qt-3.3/bin:/opt/mysql57/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin)
/root/.rbenv/plugins/ruby-build/bin/rbenv-install (ruby-build 20180329-3-g4dac7b1)
Counting installed Ruby versions: 1 versions
Checking RubyGems settings: OK
Auditing installed plugins: OK

We found that we can run rbenv init to check the problem:

rbenv init
# Load rbenv automatically by appending
# the following to ~/.bash_profile:

eval "$(rbenv init -)"

Problem solving

After debuging, We know that we have missed to append something to ~/.bash_profile,so we open ~/.bash_profile, and append the ** eval “$(rbenv init -)” ** to it, the file looks like this:

export PATH="$HOME/.rbenv/bin:$PATH"
export RBENV_VERSION=2.5.1
eval "$(rbenv init -)"

Then you can logout and login again, run this:

[[email protected] ~]# ruby -v
ruby 2.5.1p57 (2018-03-29 revision 63029) [i686-linux]

You can find detail documents about the ruby here: