On start up - error can't find gem bundler (>= 0.a) with executable bundle
Redmine version 4.0.3
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux-gnu]
kubuntu 18.04.2 64 bit
Running as user redmine, using the following command line
bundle exec server webrick -e production
when I try to start redmine I get the following error:
Traceback (most recent call last):
2: from /usr/local/bin/bundle:23:in `<main>'
1: from /usr/lib/ruby/2.5.0/rubygems.rb:308:in `activate_bin_path'
/usr/lib/ruby/2.5.0/rubygems.rb:289:in `find_spec_for_exe': can't find gem bundler (>= 0.a) with executable bundle (Gem::GemNotFoundException)
I have verified that all instances of bundler/bundle are owned by redmine, and are executable; as are all directories containing other gems, and the gems themselves.
This feels like a pathing error, but I can't find anywhere that I can explicitly set a path, not for that matter what path to set.
Thanks for your time and wisdom.