The platform is up, but one dependency path is not.

Use this when IP addressing remains online and registration, reachability, or service discovery begins to wander after a network-stack change. These issues are easy to misread because the operating system still responds while one control path, runtime dependency, or trust assumption is already out of alignment.

The symptom usually appears downstream from the real change.

• DHCP assumptions are often changed indirectly by updates, policy, hardware changes, or cleanup work that looked harmless at the time.
• DNS assumptions are often changed indirectly by updates, policy, hardware changes, or cleanup work that looked harmless at the time.
• Windows Server assumptions are often changed indirectly by updates, policy, hardware changes, or cleanup work that looked harmless at the time.
• Networking assumptions are often changed indirectly by updates, policy, hardware changes, or cleanup work that looked harmless at the time.