Error 500 after upgrade to v2026.9.0 / temporary solved by clearing browser data

Fabien_1015 · September 3, 2026, 12:31pm

Hello,

We have a discourse for the Scala PL for users which was running fine for years :

Last week, I upgraded to the latest version using "./launcher rebuild app
", since then we have very often the error “Oops - Error 500”. It appears when the website was already visited. In a browser private window, it works fine. So clearing the website data on the browser works for some time, but the problem appears again.
I tried to update 2 times discourse for the dashboard, then also to rebuild it again using “./launcher rebuild app”, but it’s still the same.
In log/rails/production.log I only see:
Started GET "/" for 127.0.0.1 at 2026-09-03 09:57:56 +0000
Processing by ListController#latest as HTML
Rendered layout layouts/application.html.erb (Duration: 391.6ms | GC: 229.5ms)
Completed 500 Internal Server Error in 474ms (Views: 392.5ms | ActiveRecord: 0.0ms (0 queries, 0 cached) | GC: 236.0ms)

Any idea what’s wrong and what I could do to solve the problem?
Thanks a lot!

Fabien

Fabien_1015 · September 3, 2026, 3:45pm

Looking deeper, deleting the _t cookie remove the “error 500”, but the error appears again when logged after maybe around 1h.

merefield · September 3, 2026, 4:07pm

v2026.9.0 has not been release yet - are you referring to the development/latest version?

Fabien_1015 · September 3, 2026, 4:20pm

I’ve not set any specific version, so I guess by default it should be latest (according to "tests-passed" is now "latest" ).
In the dashboard, this is the version I get at the bottom.

merefield · September 3, 2026, 5:18pm

In /logs, can you find the 500 error and share the error and its backtrace?

Fabien_1015 · September 7, 2026, 8:43am

I only have that in the logs (production.log), nothing elsewhere:
Started GET "/" for 127.0.0.1 at 2026-09-07 08:05:50 +0000
Processing by ListController#latest as HTML
Rendered layout layouts/application.html.erb (Duration: 164.0ms | GC: 13.5ms)
Completed 500 Internal Server Error in 248ms (Views: 164.7ms | ActiveRecord: 0.0ms (0 queries, 0 cached) | GC: 15.9ms)

I couldn’t find a way to add more debug.

BTW, I also tried to use /safe-mode but it doesn’t change anything…

merefield · September 7, 2026, 8:47am

It’s on the route /logs unless that is failing too.

Fabien_1015 · September 7, 2026, 8:54am

Sorry, I was looking at the container logs.
Here they are:

Message (18 copies reported)

PG::InvalidTextRepresentation (ERROR:  invalid input syntax for type inet: "unix:"
LINE 7:     client_ip = 'unix:',
^
)
lib/mini_sql_multisite_connection.rb:109:in 'MiniSqlMultisiteConnection#run'
app/models/user_auth_token.rb:244:in 'UserAuthToken#rotate!'
lib/auth/default_current_user_provider.rb:260:in 'Auth::DefaultCurrentUserProvider#refresh_session'
lib/current_user.rb:52:in 'CurrentUser#refresh_session'
app/controllers/application_controller.rb:91:in 'ApplicationController#perform_refresh_session'
app/controllers/application_controller.rb:444:in 'block in ApplicationController#with_resolved_locale'
app/controllers/application_controller.rb:444:in 'ApplicationController#with_resolved_locale'
app/controllers/application_controller.rb:1126:in 'ApplicationController#ensure_dont_cache_page'
lib/middleware/omniauth_bypass_middleware.rb:35:in 'Middleware::OmniauthBypassMiddleware#call'
lib/middleware/crawler_hooks.rb:13:in 'Middleware::CrawlerHooks#call'
lib/content_security_policy/middleware.rb:12:in 'ContentSecurityPolicy::Middleware#call'
lib/middleware/anonymous_cache.rb:431:in 'Middleware::AnonymousCache#call'
lib/middleware/csp_script_nonce_injector.rb:13:in 'Middleware::CspScriptNonceInjector#call'
lib/middleware/track_view_session_id_injector.rb:12:in 'Middleware::TrackViewSessionIdInjector#call'
config/initializers/008-rack-cors.rb:14:in 'Discourse::Cors#call'
lib/middleware/default_headers.rb:13:in 'Middleware::DefaultHeaders#call'
config/initializers/100-quiet_logger.rb:20:in 'DiscourseRackQuietAssetsLogger#call'
config/initializers/100-silence_logger.rb:29:in 'SilenceLogger#call'
lib/middleware/enforce_hostname.rb:23:in 'Middleware::EnforceHostname#call'
lib/middleware/request_tracker.rb:381:in 'Middleware::RequestTracker#call'
lib/middleware/overload_protections.rb:18:in 'Middleware::OverloadProtections#call'
lib/middleware/processing_request.rb:14:in 'Middleware::ProcessingRequest#call'

Backtrace

rack-mini-profiler (4.0.1) lib/patches/db/pg/alias_method.rb:112:in 'PG::Connection#exec'
rack-mini-profiler (4.0.1) lib/patches/db/pg/alias_method.rb:112:in 'PG::Connection#async_exec'
mini_sql (1.6.0) lib/mini_sql/postgres/connection.rb:217:in 'MiniSql::Postgres::Connection#run'
mini_sql (1.6.0) lib/mini_sql/active_record_postgres/connection.rb:38:in 'block in MiniSql::ActiveRecordPostgres::Connection#run'
mini_sql (1.6.0) lib/mini_sql/active_record_postgres/connection.rb:34:in 'block in MiniSql::ActiveRecordPostgres::Connection#with_lock'
activesupport (8.0.5.1) lib/active_support/concurrency/null_lock.rb:9:in 'ActiveSupport::Concurrency::NullLock#synchronize'
mini_sql (1.6.0) lib/mini_sql/active_record_postgres/connection.rb:34:in 'MiniSql::ActiveRecordPostgres::Connection#with_lock'
mini_sql (1.6.0) lib/mini_sql/active_record_postgres/connection.rb:38:in 'MiniSql::ActiveRecordPostgres::Connection#run'
lib/mini_sql_multisite_connection.rb:109:in 'MiniSqlMultisiteConnection#run'
mini_sql (1.6.0) lib/mini_sql/postgres/connection.rb:196:in 'MiniSql::Postgres::Connection#exec'
app/models/user_auth_token.rb:244:in 'UserAuthToken#rotate!'
lib/auth/default_current_user_provider.rb:260:in 'Auth::DefaultCurrentUserProvider#refresh_session'
lib/current_user.rb:52:in 'CurrentUser#refresh_session'
app/controllers/application_controller.rb:91:in 'ApplicationController#perform_refresh_session'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:361:in 'block in ActiveSupport::Callbacks::CallTemplate::MethodCall#make_lambda'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:207:in 'ActiveSupport::Callbacks::Filters::After#call'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:563:in 'block in ActiveSupport::Callbacks::CallbackSequence#invoke_after'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:563:in 'Array#each'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:563:in 'ActiveSupport::Callbacks::CallbackSequence#invoke_after'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:134:in 'block in ActiveSupport::Callbacks#run_callbacks'
app/controllers/application_controller.rb:444:in 'block in ApplicationController#with_resolved_locale'
i18n (1.15.2) lib/i18n.rb:383:in 'I18n::Base#with_locale'
app/controllers/application_controller.rb:444:in 'ApplicationController#with_resolved_locale'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:129:in 'block in ActiveSupport::Callbacks#run_callbacks'
app/controllers/application_controller.rb:1126:in 'ApplicationController#ensure_dont_cache_page'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:129:in 'block in ActiveSupport::Callbacks#run_callbacks'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:140:in 'ActiveSupport::Callbacks#run_callbacks'
actionpack (8.0.5.1) lib/abstract_controller/callbacks.rb:260:in 'AbstractController::Callbacks#process_action'
actionpack (8.0.5.1) lib/action_controller/metal/rescue.rb:27:in 'ActionController::Rescue#process_action'
actionpack (8.0.5.1) lib/action_controller/metal/instrumentation.rb:76:in 'block in ActionController::Instrumentation#process_action'
activesupport (8.0.5.1) lib/active_support/notifications.rb:210:in 'block in ActiveSupport::Notifications.instrument'
activesupport (8.0.5.1) lib/active_support/notifications/instrumenter.rb:58:in 'ActiveSupport::Notifications::Instrumenter#instrument'
activesupport (8.0.5.1) lib/active_support/notifications.rb:210:in 'ActiveSupport::Notifications.instrument'
actionpack (8.0.5.1) lib/action_controller/metal/instrumentation.rb:75:in 'ActionController::Instrumentation#process_action'
actionpack (8.0.5.1) lib/action_controller/metal/params_wrapper.rb:259:in 'ActionController::ParamsWrapper#process_action'
activerecord (8.0.5.1) lib/active_record/railties/controller_runtime.rb:39:in 'ActiveRecord::Railties::ControllerRuntime#process_action'
actionpack (8.0.5.1) lib/abstract_controller/base.rb:152:in 'AbstractController::Base#process'
actionview (8.0.5.1) lib/action_view/rendering.rb:40:in 'ActionView::Rendering#process'
rack-mini-profiler (4.0.1) lib/mini_profiler/profiling_methods.rb:116:in 'block in ActionController::Base#profile_method'
actionpack (8.0.5.1) lib/action_controller/metal.rb:252:in 'ActionController::Metal#dispatch'
actionpack (8.0.5.1) lib/action_controller/metal.rb:335:in 'ActionController::Metal.dispatch'
actionpack (8.0.5.1) lib/action_dispatch/routing/route_set.rb:67:in 'ActionDispatch::Routing::RouteSet::Dispatcher#dispatch'
actionpack (8.0.5.1) lib/action_dispatch/routing/route_set.rb:50:in 'ActionDispatch::Routing::RouteSet::Dispatcher#serve'
actionpack (8.0.5.1) lib/action_dispatch/routing/mapper.rb:32:in 'block in class:Constraints'
actionpack (8.0.5.1) lib/action_dispatch/routing/mapper.rb:62:in 'ActionDispatch::Routing::Mapper::Constraints#serve'
actionpack (8.0.5.1) lib/action_dispatch/journey/router.rb:53:in 'block in ActionDispatch::Journey::Router#serve'
actionpack (8.0.5.1) lib/action_dispatch/journey/router.rb:133:in 'block in ActionDispatch::Journey::Router#find_routes'
actionpack (8.0.5.1) lib/action_dispatch/journey/router.rb:126:in 'Array#each'
actionpack (8.0.5.1) lib/action_dispatch/journey/router.rb:126:in 'ActionDispatch::Journey::Router#find_routes'
actionpack (8.0.5.1) lib/action_dispatch/journey/router.rb:34:in 'ActionDispatch::Journey::Router#serve'
actionpack (8.0.5.1) lib/action_dispatch/routing/route_set.rb:908:in 'ActionDispatch::Routing::RouteSet#call'
lib/middleware/omniauth_bypass_middleware.rb:35:in 'Middleware::OmniauthBypassMiddleware#call'
lib/middleware/crawler_hooks.rb:13:in 'Middleware::CrawlerHooks#call'
rack (2.2.24) lib/rack/tempfile_reaper.rb:15:in 'Rack::TempfileReaper#call'
rack (2.2.24) lib/rack/conditional_get.rb:27:in 'Rack::ConditionalGet#call'
rack (2.2.24) lib/rack/head.rb:12:in 'Rack::Head#call'
actionpack (8.0.5.1) lib/action_dispatch/http/permissions_policy.rb:38:in 'ActionDispatch::PermissionsPolicy::Middleware#call'
lib/content_security_policy/middleware.rb:12:in 'ContentSecurityPolicy::Middleware#call'
lib/middleware/anonymous_cache.rb:431:in 'Middleware::AnonymousCache#call'
lib/middleware/csp_script_nonce_injector.rb:13:in 'Middleware::CspScriptNonceInjector#call'
lib/middleware/track_view_session_id_injector.rb:12:in 'Middleware::TrackViewSessionIdInjector#call'
config/initializers/008-rack-cors.rb:14:in 'Discourse::Cors#call'
rack (2.2.24) lib/rack/session/abstract/id.rb:266:in 'Rack::Session::Abstract::Persisted#context'
rack (2.2.24) lib/rack/session/abstract/id.rb:260:in 'Rack::Session::Abstract::Persisted#call'
actionpack (8.0.5.1) lib/action_dispatch/middleware/cookies.rb:706:in 'ActionDispatch::Cookies#call'
actionpack (8.0.5.1) lib/action_dispatch/middleware/callbacks.rb:31:in 'block in ActionDispatch::Callbacks#call'
activesupport (8.0.5.1) lib/active_support/callbacks.rb:100:in 'ActiveSupport::Callbacks#run_callbacks'
actionpack (8.0.5.1) lib/action_dispatch/middleware/callbacks.rb:30:in 'ActionDispatch::Callbacks#call'
actionpack (8.0.5.1) lib/action_dispatch/middleware/debug_exceptions.rb:31:in 'ActionDispatch::DebugExceptions#call'
actionpack (8.0.5.1) lib/action_dispatch/middleware/show_exceptions.rb:32:in 'ActionDispatch::ShowExceptions#call'
logster (2.21.0) lib/logster/middleware/reporter.rb:40:in 'Logster::Middleware::Reporter#call'
lib/middleware/default_headers.rb:13:in 'Middleware::DefaultHeaders#call'
railties (8.0.5.1) lib/rails/rack/logger.rb:41:in 'Rails::Rack::Logger#call_app'
railties (8.0.5.1) lib/rails/rack/logger.rb:29:in 'Rails::Rack::Logger#call'
config/initializers/100-quiet_logger.rb:20:in 'DiscourseRackQuietAssetsLogger#call'
config/initializers/100-silence_logger.rb:29:in 'SilenceLogger#call'
actionpack (8.0.5.1) lib

and

Message (209 copies reported)

Job exception: ERROR:  invalid input syntax for type inet: "unix:"
LINE 2: SET ip_address = 'unix:'
^

Backtrace

/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/rack-mini-profiler-4.0.1/lib/patches/db/pg/alias_method.rb:109:in 'PG::Connection#exec'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/rack-mini-profiler-4.0.1/lib/patches/db/pg/alias_method.rb:109:in 'PG::Connection#async_exec'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/mini_sql-1.6.0/lib/mini_sql/postgres/connection.rb:217:in 'MiniSql::Postgres::Connection#run'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/mini_sql-1.6.0/lib/mini_sql/active_record_postgres/connection.rb:38:in 'block in MiniSql::ActiveRecordPostgres::Connection#run'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/mini_sql-1.6.0/lib/mini_sql/active_record_postgres/connection.rb:34:in 'block in MiniSql::ActiveRecordPostgres::Connection#with_lock'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/activesupport-8.0.5.1/lib/active_support/concurrency/null_lock.rb:9:in 'ActiveSupport::Concurrency::NullLock#synchronize'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/mini_sql-1.6.0/lib/mini_sql/active_record_postgres/connection.rb:34:in 'MiniSql::ActiveRecordPostgres::Connection#with_lock'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/mini_sql-1.6.0/lib/mini_sql/active_record_postgres/connection.rb:38:in 'MiniSql::ActiveRecordPostgres::Connection#run'
/var/www/discourse/lib/mini_sql_multisite_connection.rb:109:in 'MiniSqlMultisiteConnection#run'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/mini_sql-1.6.0/lib/mini_sql/postgres/connection.rb:196:in 'MiniSql::Postgres::Connection#exec'
/var/www/discourse/app/models/user.rb:1142:in 'User.update_ip_address!'
/var/www/discourse/lib/auth/default_current_user_provider.rb:235:in 'block in Auth::DefaultCurrentUserProvider#current_user'
/var/www/discourse/lib/scheduler/defer.rb:135:in 'block in Scheduler::Deferrable#do_work'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/rails_multisite-9.0.0/lib/rails_multisite/connection_management/null_instance.rb:54:in 'RailsMultisite::ConnectionManagement::NullInstance#with_connection'
/var/www/discourse/vendor/bundle/ruby/3.4.0/gems/rails_multisite-9.0.0/lib/rails_multisite/connection_management.rb:23:in 'RailsMultisite::ConnectionManagement.with_connection'
/var/www/discourse/lib/scheduler/defer.rb:130:in 'Scheduler::Deferrable#do_work'
/var/www/discourse/lib/scheduler/defer.rb:116:in 'block (2 levels) in Scheduler::Deferrable#start_thread'

merefield · September 7, 2026, 9:06am

Are you operating some kind of proxy - can you describe the architecture?

Looks like you are trying to pass the string “unix:” to the ip_address field …

This could be a misconfiguration upstream of Discourse.

There was a similar issue reported, and solved here which related to Caddy:

Fabien_1015 · September 7, 2026, 10:38am

Thanks a lot for the help!

I have exactly this configuration:

… except it was missing the “proxy_set_header X-Real-IP $remote_addr;”.

So, I guess it could be related.
It seems to work ok now. I’ll do more tests and report it tomorrow if this solves the issue.
Thanks!

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Error 500 after upgrade to v2026.9.0 / temporary solved by clearing browser data

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