Focused, hands-on DevOps and server-side problems with hints, feedback, and automated solution checks.
Sometimes you need an app to talk to a different backend, but its configuration is unknown or the destination address is hard-coded. Practice overriding hostname resolution for a single Docker container to redirect its requests without modifying the app or rebuilding its image.
An internal service started receiving requests from unexpected IP addresses. Identify the unexpected sources and find out which systems are behind them.
Practice manually resolving public domains, internal hostnames, and locally defined names to the corresponding IP addresses so you feel confident next time a DNS issue occurs.
Learn how to reconfigure the Kubernetes cluster DNS domain by updating CoreDNS ConfigMap and kubelet configuration on all nodes, a critical skill for custom cluster networking and CKA exam preparation.
