Sindarina, Edge Case DetectiveSince I just saw yet another developer use '1.2.3.4' in an example configuration, a reminder that you MUST NOT use publicly routable addresses that you do not control in your code.
Instead, use one of the available 'TEST-NET' IPv4 or IPv6 ranges documented in RFC 6890, such as;
192.0.2.0/24
198.51.100.0/24
203.0.113.0/24
❌ 1.2.3.4
✅ 192.0.2.4
Pass it on to all of your fellow developers, documentation writers, and so forth.
Full RFC is here;
RFC 6890: Special-Purpose IP Address Registries
This memo reiterates the assignment of an IPv4 address block (192.0.0.0/24) to IANA. It also instructs IANA to restructure its IPv4 and IPv6 Special-Purpose Address Registries. Upon restructuring, the aforementioned registries will record all special-purpose address blocks, maintaining a common set of information regarding each address block.
Michael W Lucas 
Tux 
🪿