I was installing Opennebula 5.6 on an additional Centos7 node to expand my cloud and suddenly
when I executed the step to install gems I am getting an error
[root@localhost ~]# /usr/share/one/install_gems Fetching: bundler-2.0.1.gem (100%) ERROR: Error installing bundler: bundler requires Ruby version >= 2.3.0. /usr/share/one/install_gems:413:in `install_bundler_gem': undefined method `new' for #<IO:<STDERR>> (NoMethodError) from /usr/share/one/install_gems:592:in `<main>'
I was stuck - Centos7 latest Ruby is 2.0.0
[root@localhost ~]# rpm -q ruby ruby-184.108.40.2068-35.el7_6.x86_64
However have 3 other Centos7 nodes running Opennebula, same rpm version but I didn’t have such error before.
This allowed me to work around the problem, by forcing same bundler gem version as I have on other nodes,
gem install bundler -v 1.16.4
I could continue with
So, to avoid this problem in the future /usr/share/one/install_gems should have bundler version forced to 1.16.4