What is the Difference Between 127.0.0.1 and 0.0.0.0?
- 127.0.0.1 is the loopback address (also known as localhost).
- 0.0.0.0 is a non-routable meta-address used to designate an invalid, unknown, or non-applicable target (a ‘no particular address’ place holder).
In the context of a route entry, it usually means the default route.
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.
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