alt Hacker NewsHasn’t everyone moved on to ULAs now?
To explain, IPv6 link local addresses are like using a MAC address to send packets. You wouldn’t ever host services on a LL address and things that do are doing it wrong. Every v6 router should advertise a ULA prefix to all downstream clients. If you want to connect to your router’s web UI you’d use its universal local address—not its link local—and avoid all of these problems. This is exactly why zones were deemed mistake and replaced by ULAs and this was 10 years ago… at least!
Replies
topranks • today at 8:14 AM
ULAs are standards compliant but tbh it's a layer of complexity I rather not have.
Just give me GUAs and be done with it.
➕ show 1 reply
Having services be accessible on a link-local address and then advertising that service via mDNS is a completely legitimate use-case that works extremely well and is extremely common with Apple devices amongst others. The advantage being that it still works just the same even without a router handing out addresses or if you just connect two devices directly to each other.
Also what gives you the impression that zones were “deemed a mistake”? They may be awkward in URIs but they are very much not a mistake, they are a deliberate part of ensuring that each link has its own link-local subnet without any ambiguity. It solves the problem of what the operating system should do if you need to access a link-local address that shows up via more than one network interface, which is a very real problem with unscoped IPv4 link-local addresses.
Finally, ULAs don’t and were never intended to replace link-local addresses, they serve a different purpose entirely.