Foreman and foreman-proxy are both 1.5.2, along with isc-dhcp-server.

In the UI:

Select a host -> Edit -> Network -> Change the IP address to an available IP -> Receive error: "Unable to save\nCreate DHCP Settings for host.domain task failed with the following error: ERF12-6899 [ProxyAPI::ProxyException]: Unable to set DHCP entry ([RestClient::Conflict]: 409 Conflict) for proxy https://dhcp.domain:8443/dhcp"

From foreman:/var/log/foreman/production.log:

Delete DHCP reservation for host.domain-00:1e:c9:2c:43:c3/xxx.xxx.xxx.193
Create DHCP reservation for host.domain-00:1e:c9:2c:43:c3/xxx.xxx.xxx.194
Create DHCP Settings for host.domain task failed with the following error: ERF12-6899 [ProxyAPI::ProxyException]: Unable to set DHCP entry ([RestClient::Conflict]: 409 Conflict) for proxy https://dhcp.domain:8443/dhcp/usr/share/foreman/lib/proxy_api/dhcp.rb:66:in `set'
/usr/share/foreman/lib/net/dhcp/record.rb:28:in `create'
/usr/share/foreman/app/models/concerns/orchestration/dhcp.rb:22:in `set_dhcp'
/usr/share/foreman/app/models/concerns/orchestration.rb:137:in `send'
/usr/share/foreman/app/models/concerns/orchestration.rb:137:in `execute'
/usr/share/foreman/app/models/concerns/orchestration.rb:85:in `process'
/usr/share/foreman/app/models/concerns/orchestration.rb:77:in `each'
/usr/share/foreman/app/models/concerns/orchestration.rb:77:in `process'
/usr/share/foreman/app/models/concerns/orchestration.rb:18:in `on_save'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:660:in `_run__1120636067__save__4__callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:405:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:405:in `__run_callback'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:385:in `_run_save_callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:81:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:81:in `run_callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/callbacks.rb:264:in `create_or_update'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/persistence.rb:84:in `save'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/validations.rb:50:in `save'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/attribute_methods/dirty.rb:22:in `save'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:259:in `save_without_type'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:313:in `with_transaction_returning_status'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:208:in `transaction'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:311:in `with_transaction_returning_status'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:259:in `save_without_type'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:270:in `rollback_active_record_state!'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:258:in `save_without_type'
/usr/share/foreman/app/models/concerns/foreman/sti.rb:29:in `save'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/persistence.rb:217:in `update_attributes'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:313:in `with_transaction_returning_status'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:208:in `transaction'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/transactions.rb:311:in `with_transaction_returning_status'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/persistence.rb:215:in `update_attributes'
/usr/share/foreman/app/controllers/hosts_controller.rb:113:in `update'
/usr/share/foreman/app/models/taxonomy.rb:41:in `no_taxonomy_scope'
/usr/share/foreman/app/models/taxonomy.rb:48:in `as_taxonomy'
/usr/share/foreman/app/models/concerns/foreman/thread_session.rb:143:in `as_location'
/usr/share/foreman/app/models/taxonomy.rb:47:in `as_taxonomy'
/usr/share/foreman/app/models/concerns/foreman/thread_session.rb:108:in `as_org'
/usr/share/foreman/app/models/taxonomy.rb:46:in `as_taxonomy'
/usr/share/foreman/app/models/taxonomy.rb:40:in `no_taxonomy_scope'
/usr/share/foreman/app/controllers/hosts_controller.rb:105:in `update'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal/implicit_render.rb:4:in `send_action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal/implicit_render.rb:4:in `send_action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/abstract_controller/base.rb:167:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal/rendering.rb:10:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/abstract_controller/callbacks.rb:18:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:549:in `_run__1589944314__process_action__2067640602__callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:215:in `_conditional_callback_around_6381'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:326:in `around'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:310:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:310:in `_callback_around_5274'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:214:in `_conditional_callback_around_6381'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:526:in `_run__1589944314__process_action__2067640602__callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:215:in `_conditional_callback_around_6380'
/usr/share/foreman/app/models/concerns/foreman/thread_session.rb:33:in `clear_thread'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:214:in `_conditional_callback_around_6380'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:415:in `_run__1589944314__process_action__2067640602__callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:215:in `_conditional_callback_around_6379'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:326:in `around'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:310:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:310:in `_callback_around_13'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:214:in `_conditional_callback_around_6379'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:414:in `_run__1589944314__process_action__2067640602__callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:405:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:405:in `__run_callback'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:81:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:81:in `run_callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/abstract_controller/callbacks.rb:17:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal/rescue.rb:29:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal/instrumentation.rb:30:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/notifications.rb:123:in `instrument'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/notifications.rb:123:in `instrument'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal/instrumentation.rb:29:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal/params_wrapper.rb:207:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/railties/controller_runtime.rb:18:in `process_action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/abstract_controller/base.rb:121:in `process'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/abstract_controller/rendering.rb:45:in `process'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal.rb:203:in `dispatch'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_controller/metal.rb:246:in `action'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/routing/route_set.rb:73:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/routing/route_set.rb:36:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/journey-1.0.4/lib/journey/router.rb:68:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/journey-1.0.4/lib/journey/router.rb:56:in `each'
/usr/share/foreman/vendor/ruby/1.8/gems/journey-1.0.4/lib/journey/router.rb:56:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/routing/route_set.rb:608:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/apipie-rails-0.1.3/lib/apipie/static_dispatcher.rb:65:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/apipie-rails-0.1.3/lib/apipie/middleware/checksum_in_headers.rb:27:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/etag.rb:23:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/conditionalget.rb:35:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/head.rb:14:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/params_parser.rb:21:in `call'
/usr/share/foreman/lib/middleware/catch_json_parse_errors.rb:9:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/flash.rb:242:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/session/abstract/id.rb:210:in `context'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/session/abstract/id.rb:205:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/cookies.rb:341:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/query_cache.rb:64:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/activerecord-3.2.18/lib/active_record/connection_adapters/abstract/connection_pool.rb:479:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/callbacks.rb:28:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:405:in `_run__25082136__call__4__callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:405:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:405:in `__run_callback'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:81:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/callbacks.rb:81:in `run_callbacks'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/callbacks.rb:27:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/railties-3.2.18/lib/rails/rack/logger.rb:32:in `call_app'
/usr/share/foreman/vendor/ruby/1.8/gems/railties-3.2.18/lib/rails/rack/logger.rb:16:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/tagged_logging.rb:22:in `tagged'
/usr/share/foreman/vendor/ruby/1.8/gems/railties-3.2.18/lib/rails/rack/logger.rb:16:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/request_id.rb:22:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/methodoverride.rb:21:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/runtime.rb:17:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/activesupport-3.2.18/lib/active_support/cache/strategy/local_cache.rb:72:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/lock.rb:15:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/actionpack-3.2.18/lib/action_dispatch/middleware/static.rb:63:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-cache-1.2/lib/rack/cache/context.rb:136:in `forward'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-cache-1.2/lib/rack/cache/context.rb:143:in `pass'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-cache-1.2/lib/rack/cache/context.rb:155:in `invalidate'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-cache-1.2/lib/rack/cache/context.rb:71:in `call!'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-cache-1.2/lib/rack/cache/context.rb:51:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/railties-3.2.18/lib/rails/engine.rb:484:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/railties-3.2.18/lib/rails/application.rb:231:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/railties-3.2.18/lib/rails/railtie/configurable.rb:30:in `send'
/usr/share/foreman/vendor/ruby/1.8/gems/railties-3.2.18/lib/rails/railtie/configurable.rb:30:in `method_missing'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/urlmap.rb:64:in `call'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/urlmap.rb:49:in `each'
/usr/share/foreman/vendor/ruby/1.8/gems/rack-1.4.5/lib/rack/urlmap.rb:49:in `call'
/usr/lib/ruby/1.8/phusion_passenger/rack/request_handler.rb:92:in `process_request'
/usr/lib/ruby/1.8/phusion_passenger/abstract_request_handler.rb:207:in `main_loop'
/usr/lib/ruby/1.8/phusion_passenger/rack/application_spawner.rb:118:in `run'
/usr/lib/ruby/1.8/phusion_passenger/rack/application_spawner.rb:65:in `spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/utils.rb:184:in `safe_fork'
/usr/lib/ruby/1.8/phusion_passenger/rack/application_spawner.rb:58:in `spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/rack/application_spawner.rb:41:in `spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/spawn_manager.rb:159:in `spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/spawn_manager.rb:287:in `handle_spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:352:in `__send__'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:352:in `main_loop'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:196:in `start_synchronously'
/usr/lib/phusion_passenger/passenger-spawn-server:61
Rolling back due to a problem: Create DHCP Settings for host.domain 9 failed host.domainset_dhcp
Create DHCP reservation for host.domain-00:1e:c9:2c:43:c3/xxx.xxx.xxx.193

From dhcp.domain:/var/log/foreman-proxy/foreman-proxy.log:
W, [2014-08-12T09:45:01.597397 #31129] WARN -- : Request to create a conflicting record
D, [2014-08-12T09:45:01.597521 #31129] DEBUG -- : request: {"mac"=>"00:1e:c9:2c:43:c3", "nextServer"=>"yyy.yyy.yyy.146", "hostname"=>"host.domain", "ip"=>"xxx.xxx.xxx.194", "filename"=>"pxelinux.0"}
D, [2014-08-12T09:45:01.597638 #31129] DEBUG -- : local: {:mac=>"00:1e:c9:2c:43:c3", :subnet=>xxx.xxx.xxx.0/255.255.255.0, :nextServer=>"yyy.yyy.yyy.146", :filename=>"pxelinux.0", :hostname=>"host.domain", :ip=>"xxx.xxx.xxx.193"}
E, [2014-08-12T09:45:01.598006 #31129] ERROR -- : Record xxx.xxx.xxx.0/128.101.154.194 already exists
D, [2014-08-12T09:45:01.598159 #31129] DEBUG -- : /usr/share/foreman-proxy/bin/../lib/proxy/dhcp/server.rb:110:in `addRecord'
/usr/share/foreman-proxy/bin/../lib/proxy/dhcp/server/isc.rb:27:in `addRecord'
/usr/share/foreman-proxy/bin/../lib/dhcp_api.rb:94:in `POST /dhcp/:network'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:1151:in `call'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:1151:in `compile!'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:724:in `instance_eval'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:724:in `route_eval'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:708:in `route!'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:758:in `process_route'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:755:in `catch'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:755:in `process_route'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:707:in `route!'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:706:in `each'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:706:in `route!'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:843:in `dispatch!'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:644:in `call!'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:808:in `instance_eval'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:808:in `invoke'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:808:in `catch'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:808:in `invoke'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:644:in `call!'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:629:in `call'
/usr/lib/ruby/vendor_ruby/rack/methodoverride.rb:24:in `call'
/usr/lib/ruby/vendor_ruby/rack/head.rb:9:in `call'
/usr/lib/ruby/vendor_ruby/rack/commonlogger.rb:20:in `call'
/usr/lib/ruby/vendor_ruby/sinatra/showexceptions.rb:21:in `call'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:1272:in `call'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:1303:in `synchronize'
/usr/lib/ruby/vendor_ruby/sinatra/base.rb:1272:in `call'
/usr/lib/ruby/vendor_ruby/rack/handler/webrick.rb:59:in `service'
/usr/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
/usr/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
/usr/lib/ruby/1.8/webrick/server.rb:173:in `start_thread'
/usr/lib/ruby/1.8/webrick/server.rb:162:in `start'
/usr/lib/ruby/1.8/webrick/server.rb:162:in `start_thread'
/usr/lib/ruby/1.8/webrick/server.rb:95:in `start'
/usr/lib/ruby/1.8/webrick/server.rb:92:in `each'
/usr/lib/ruby/1.8/webrick/server.rb:92:in `start'
/usr/lib/ruby/1.8/webrick/server.rb:23:in `start'
/usr/lib/ruby/1.8/webrick/server.rb:82:in `start'
/usr/lib/ruby/vendor_ruby/rack/handler/webrick.rb:13:in `run'
/usr/share/foreman-proxy/bin/../lib/sinatra-patch.rb:42:in `run!'
/usr/share/foreman-proxy/bin/smart-proxy:44

Excpectation: Changing a host's IP in the web UI should delete and re-create the dhcp lease in /var/lib/dhcp/dhcpd.leases
Reality: Errors and an unchanged entry in /var/lib/dhcp/dhcpd.leases