Best Fixes
Confirm the target service is actually running and listening on the expected interface and port.
Check local firewalls, container port mappings, and whether the app is only bound to localhost when it should be reachable elsewhere.
Error Fix
How to Fix 'Connection refused'
A quick framework for determining whether the service is down, bound incorrectly, or blocked locally.
Connection refused means the target host was reachable, but nothing accepted the connection on that port. That usually points to a service state, bind address, or local networking issue rather than DNS.
Avoid This
Do not waste time on DNS debugging if the error already proves the host was reached.
Do not assume the port mapping is correct just because the container or process is running.
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