Transcript
False meme image that says “bad news ipv4 fans. linus torvalds has announced removing ipv4 support from the linux kernel after the maintainers of the network stack got into a fight over WHAT KIND OF HRT gives the best results. this incident will impact 5 billion people and will make 95% of all network equipment on Earth binnable.” with fake screenshots of the linux kernel mailing list a girl calling another one a slur from 4chan over HRT choices and Linus Torvalds saying he will drop IPv4 support and asking the maintainers to learn to shut the fuck up.
That’s a link local address [0].
That’s a ULA [1]
This one is a globally routable address (Global Unicast Address, or GUA) [2].
As you observed, link-local addresses are generated completely independently. ULAs and GUAs are self-assigned using SLAAC or assigned by a server using DHCPv6 after your host has seen a router.
For a GUA or ULA to be assigned, the router or DHCP server has to have a prefix delegated to it. A GUA prefix would come from your ISP. A ULA prefix would be configured on the router itself. If yours has one without you setting it up, maybe it does that by default?
[0] https://en.wikipedia.org/wiki/Link-local_address [1] https://en.wikipedia.org/wiki/Unique_local_address [2] https://www.iana.org/assignments/ipv6-unicast-address-assignments/ipv6-unicast-address-assignments.xhtml
Yeah, I guess my router just decided on an ULA prefix on its own. Thank you for providing the right terminology and explaining how a host gets these addresses.