Interesting bit of networking interface minutiae. Not sure what practical uses it could have for us, but good to know
0.0.0.0 is not an alias for 127.0.0.1. See:
In the context of servers, 0.0.0.0 means “all IPv4 addresses on the local machine”. If a host has two IP addresses, 192.168.1.1 and 10.1.2.1, and a server running on the host listens on 0.0.0.0, it will be reachable at both of those IPs.
Listening on 0.0.0.0 rather than 127.0.0.1 can be a security risk for anything that doesn’t expect malicious network interaction from remote systems.
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