OpenNebula

Currently, this is a problem with Debian 9 and Ubuntu 17.04 packages:

systemd[1]: Starting OpenNebula Web UI Server...
systemd[1]: Started OpenNebula Web UI Server.
ruby[20516]: /var/lib/gems/2.3.0/gems/rack-2.0.3/lib/rack/show_exceptions.rb:16: warning: already initialized constant Rack::ShowExceptions::CONTEXT
ruby[20516]: /usr/lib/ruby/vendor_ruby/rack/showexceptions.rb:16: warning: previous definition of CONTEXT was here
ruby[20516]: /var/lib/gems/2.3.0/gems/rack-2.0.3/lib/rack/show_exceptions.rb:114: warning: already initialized constant Rack::ShowExceptions::TEMPLATE
ruby[20516]: /usr/lib/ruby/vendor_ruby/rack/showexceptions.rb:115: warning: previous definition of TEMPLATE was here
ruby[20516]: --------------------------------------
ruby[20516]:          Server configuration
ruby[20516]: --------------------------------------
ruby[20516]: {:tmpdir=>"/var/tmp",
ruby[20516]:  :one_xmlrpc=>"http://localhost:2633/RPC2",
ruby[20516]:  :host=>"0.0.0.0",
ruby[20516]:  :port=>9869,
ruby[20516]:  :sessions=>"memory",
ruby[20516]:  :memcache_host=>"localhost",
ruby[20516]:  :memcache_port=>11211,
ruby[20516]:  :memcache_namespace=>"opennebula.sunstone",
ruby[20516]:  :env=>"prod",
ruby[20516]:  :debug_level=>3,
ruby[20516]:  :auth=>"opennebula",
ruby[20516]:  :core_auth=>"cipher",
ruby[20516]:  :remote_version=>"http://downloads.opennebula.org/latest",
ruby[20516]:  :vnc_proxy_port=>29876,
ruby[20516]:  :vnc_proxy_support_wss=>false,
ruby[20516]:  :vnc_proxy_cert=>nil,
ruby[20516]:  :vnc_proxy_key=>nil,
ruby[20516]:  :vnc_proxy_ipv6=>false,
ruby[20516]:  :vnc_request_password=>false,
ruby[20516]:  :lang=>"en_US",
ruby[20516]:  :table_order=>"desc",
ruby[20516]:  :marketplace_url=>"http://marketplace.opennebula.systems/",
ruby[20516]:  :oneflow_server=>"http://localhost:2474/",
ruby[20516]:  :routes=>["oneflow", "vcenter", "support"],
ruby[20516]:  :session_expire_time=>3600}
ruby[20516]: --------------------------------------
ruby[20516]: /var/lib/gems/2.3.0/gems/rack-2.0.3/lib/rack/session/abstract/id.rb:202:in `<class:Persisted>': uninitialized constant Rack::Session::Abstract::Persisted::RACK_SESSION (NameError)
ruby[20516]: Did you mean?  Rack::Session
ruby[20516]: #011from /var/lib/gems/2.3.0/gems/rack-2.0.3/lib/rack/session/abstract/id.rb:200:in `<module:Abstract>'
ruby[20516]: #011from /var/lib/gems/2.3.0/gems/rack-2.0.3/lib/rack/session/abstract/id.rb:14:in `<module:Session>'
ruby[20516]: #011from /var/lib/gems/2.3.0/gems/rack-2.0.3/lib/rack/session/abstract/id.rb:12:in `<module:Rack>'
ruby[20516]: #011from /var/lib/gems/2.3.0/gems/rack-2.0.3/lib/rack/session/abstract/id.rb:10:in `<top (required)>'
ruby[20516]: #011from /usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
ruby[20516]: #011from /usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
ruby[20516]: #011from /var/lib/gems/2.3.0/gems/rack-2.0.3/lib/rack/session/pool.rb:6:in `<top (required)>'
ruby[20516]: #011from /usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
ruby[20516]: #011from /usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
ruby[20516]: #011from /usr/lib/one/sunstone/sunstone-server.rb:135:in `<main>'
systemd[1]: opennebula-sunstone.service: Main process exited, code=exited, status=1/FAILURE
systemd[1]: opennebula-sunstone.service: Unit entered failed state.
systemd[1]: opennebula-sunstone.service: Failed with result 'exit-code'.