Check the application logs and they'll confirm the problem:
kubectl logs -l app=todo-list,component=save-handler
Shows that the message handler can't connect to the queue:
Connecting to message queue url: nats://todo-list-queue:4222
Unhandled exception. NATS.Client.NATSNoServersException: Unable to connect to a server.
And:
kubectl logs -l app=todo-list,component=web --tail 100
Shows that the website can't connect to the database:
---> MySql.Data.MySqlClient.MySqlException (0x80004005): Unable to connect to any of the specified MySQL hosts
Check the configuration objects for the app to find the expected domain names for the message queue and database.
Need more? Here's the solution.