IPv6 Only Support

[Gunni]

Describe your core improvement

Add support for running without IPv4. Right now you can't compile with CONFIG_LWIP_IPV4: n but surely esphome can just ... not use IPv4? Not compile in DHCP? Work our way up?

Add a flag somewhere, maybe under network, something like network_stack with an enum value of IPv4, IPv6, all?

Current limitations

Today the build breaks if IPv4 is removed using compile flags, see: esphome/issues#6535 for details.

But I cannot find any way to have ESPHome not run DHCP without setting a static IPv4 address. Which is then used for communication that fails.

I Cannot tell esphome to not even try IPv4.

Technical benefits

• Reduces image size
• Simplifies code
• Reduces attack-surface

Additional context

It's so odd to me that in 2025, the default value of enable_ipv6 is still False, IPv6 was first specified in 1995... Almost 30 years ago...