In my LDAP configuration (Administer > LDAP Authentication) I have "ThumbnailPhoto" configured as the attribute (AD LDAP directory) however the image is not displayed in the GUI, and in the logs I see I lot of the following

2016-05-23 11:46:01 [app] [I] Started GET "/images/avatars/a4942dbf66f01a1de0e7adae1a6c8835c08f76a9.jpg" for 192.168.222.132 at 2016-05-23 11:46:01 +1200
2016-05-23 11:46:01 [app] [F]
 | ActionController::RoutingError (No route matches [GET] "/images/avatars/a4942dbf66f01a1de0e7adae1a6c8835c08f76a9.jpg"):
 |   actionpack (4.1.5) lib/action_dispatch/middleware/debug_exceptions.rb:21:in `call'
 |   actionpack (4.1.5) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
 |   railties (4.1.5) lib/rails/rack/logger.rb:38:in `call_app'
 |   railties (4.1.5) lib/rails/rack/logger.rb:22:in `call'
 |   actionpack (4.1.5) lib/action_dispatch/middleware/request_id.rb:21:in `call'
 |   rack (1.5.2) lib/rack/methodoverride.rb:21:in `call'
 |   rack (1.5.2) lib/rack/runtime.rb:17:in `call'
 |   activesupport (4.1.5) lib/active_support/cache/strategy/local_cache_middleware.rb:26:in `call'
 |   actionpack (4.1.5) lib/action_dispatch/middleware/static.rb:64:in `call'
 |   rack (1.5.2) lib/rack/sendfile.rb:112:in `call'
 |   railties (4.1.5) lib/rails/engine.rb:514:in `call'
 |   railties (4.1.5) lib/rails/application.rb:144:in `call'
 |   railties (4.1.5) lib/rails/railtie.rb:194:in `public_send'
 |   railties (4.1.5) lib/rails/railtie.rb:194:in `method_missing'
 |   rack (1.5.2) lib/rack/builder.rb:138:in `call'
 |   rack (1.5.2) lib/rack/urlmap.rb:65:in `block in call'
 |   rack (1.5.2) lib/rack/urlmap.rb:50:in `each'
 |   rack (1.5.2) lib/rack/urlmap.rb:50:in `call'
 |   /usr/share/passenger/phusion_passenger/rack/thread_handler_extension.rb:74:in `process_request'
 |   /usr/share/passenger/phusion_passenger/request_handler/thread_handler.rb:141:in `accept_and_process_next_request'
 |   /usr/share/passenger/phusion_passenger/request_handler/thread_handler.rb:109:in `main_loop'
 |   /usr/share/passenger/phusion_passenger/request_handler.rb:455:in `block (3 levels) in start_threads'
 |   logging (1.8.2) lib/logging/diagnostic_context.rb:323:in `call'
 |   logging (1.8.2) lib/logging/diagnostic_context.rb:323:in `block in create_with_logging_context'
 |

The file exists here:

/var/lib/foreman/public/assets/avatars/a4942dbf66f01a1de0e7adae1a6c8835c08f76a9.jpg

seems to be an error in the GET - /images/avatars vs /assets/avatars

Interestingly, I made the directory and copied the file to /var/lib/foreman/public/images/avatars/ and the error has disappeared from the production.log but the image is not displayed still