Remote Execution Installation Error

I have managed to install Foreman on one server and Puppet and Puppet CA on another one.
thanks to this post:
puppet master on 443

I am now trying to install Remote Execution using the foreman installer.

I am running foreman-installer --enable-foreman-plugin-remote-execution on the foreman server however it exits with error:

[ WARN 2019-09-23T14:57:04 main]  Unknown variable: 'foreman_proxy::plugin_version'. (file: /usr/share/foreman-installer/modules/foreman_proxy/manifests/plugin.pp, line: 3, column: 14)

[ WARN 2019-09-23T14:57:04 main] Unknown variable: ‘foreman_proxy::plugin_prefix’. (file: /usr/share/foreman-installer/modules/foreman_proxy/manifests/plugin.pp, line: 4, column: 17)
[ WARN 2019-09-23T14:57:04 main] Unknown variable: ‘::foreman_proxy::etc’. (file: /usr/share/foreman-installer/modules/foreman_proxy/manifests/settings_file.pp, line: 35, column: 35)
[ WARN 2019-09-23T14:57:04 main] Unknown variable: ‘::foreman_proxy::user’. (file: /usr/share/foreman-installer/modules/foreman_proxy/manifests/settings_file.pp, line: 37, column: 19)
[ERROR 2019-09-23T14:57:04 main] Evaluation Error: Error while evaluating a Resource Statement, Foreman_proxy::Settings_file[dynflow]: parameter ‘group’ expects a String value, got Undef (file: /usr/share/foreman-installer/modules/foreman_proxy/manifests/plugin/dynflow.pp, line: 48) on node foreman.xxxxxxx.info

Also running foreman-installer --enable-foreman-proxy-plugin-remote-execution-ssh on the puppet server I get:

[ERROR 2019-09-23T14:37:25 main] Systemd start for foreman-proxy failed!
[ERROR 2019-09-23T14:37:25 main] journalctl log for foreman-proxy:
[ERROR 2019-09-23T14:37:25 main] – Logs begin at Fri 2019-09-13 14:02:09 UTC, end at Mon 2019-09-23 14:37:25 UTC. –
[ERROR 2019-09-23T14:37:25 main] Sep 23 14:34:01 puppet-master systemd[1]: Stopping Foreman Proxy…
[ERROR 2019-09-23T14:37:25 main] Sep 23 14:34:01 puppet-master systemd[1]: Stopped Foreman Proxy.
[ERROR 2019-09-23T14:37:25 main] Sep 23 14:34:01 puppet-master systemd[1]: Starting Foreman Proxy…
[ERROR 2019-09-23T14:37:25 main] Sep 23 14:34:01 puppet-master smart-proxy[23469]: /usr/lib/ruby/vendor_ruby/dynflow/director.rb:16:in `block in class:Director’: uninitialized constant Concurrent::Edge::Future (NameError)
[ERROR 2019-09-23T14:37:25 main] Sep 23 14:34:01 puppet-master smart-proxy[23469]: Did you mean? Concurrent::Future

Foreman and Proxy versions: 1.23

I am not quite sure if my approach of installing the foreman plugin in one server and proxy plugin in the other is correct.

Could someone please point me to the correct procedure?

many thanks

Mauro

I know this is four months later, but still I wanted to share my thoughts:
You seem to have bumped into the problem described here: Bug #25716: Foreman-proxy is missing ruby-logging dependency - Packaging - Foreman

Unfortunately, there is no easy solution at the moment but Stephan Eicher describes a workaround if my memory serves me well:
Make sure ruby-concurrent will be installed before any foreman component:

package {'ruby-logging':
  ensure => present,
  before => [Package['foreman-postgresql'], Package['foreman-proxy']],
}

I actually encountered a differnt error installing remote execution plugin that I haven’t been able to solve yet. So mind that there may be other obstacles.

/usr/lib/ruby/vendor_ruby/foreman_tasks_core/ticker.rb:2:in `<module:ForemanTasksCore>': uninitialized constant Dynflow (NameError)

If you broke your foreman setup, remove the newly isntalled plugins and rerun foreman-installer

$ apt-get auto remove ruby-foreman-remote-execution ruby-smart-proxy-remote-execution-ssh
$ foreman-installer