I have a recently installed RHEL7 system, and need to do gem install jekyll, however this fails as:
Fetching: yajl-ruby-1.2.1.gem (100%)
Building native extensions. This could take a while...
ERROR: Error installing jekyll:
ERROR: Failed to build gem native extension.
/usr/bin/ruby extconf.rb
mkmf.rb can't find header files for ruby at /usr/share/include/ruby.h
Google suggest this is due to the lack of a ruby-devel package being installed. However there doesn't seem to be such a package in RHEL7. Do I need to move to a software collection (don't really want to do this as this will be for a production machine, not development) or can I get it some other way?
Install ruby package on your system and try again.