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Re:IPv6 Is Hard by kllrnohj on Sunday February 16, 2025 @01:42PM (#43070418)
that's not mDNS that's just dhcp+dns and it's something ipv6 actually breaks, which is part of the problem. DHCPv6 is optional, so local devices don't necessarily ever register their hostname nor do they necessarily ever consider your local DNS server.
Re:IPv6 Is Hard by amaccuish on Sunday February 16, 2025 @01:50PM (#43070490)
>that's not mDNS that's just dhcp+dns

Actually mDNS does exactly what they said just fine. You’re confusing it with the ability of a DHCP server to make updates in DNS on behalf of clients. There is more than one way to skin the cat. Both achieve the same affect, just differently.

> nor do they necessarily ever consider your local DNS server.

Hardcoded DNS servers are just as equally a thing with IPv4.

Re:IPv6 Is Hard by kllrnohj on Sunday February 16, 2025 @04:05PM (#43071702)
> Hardcoded DNS servers are just as equally a thing with IPv4.

Of course, but they aren't the baseline expectation like it is with ipv6 since ipv6 baseline assumption is SLAAC. And SLAAC is terrible. If you control all the devices on the network, like a cloud install, you can just pretend SLAAC doesn't exist and live in a much better world.

If it's a home network then you're stuck expecting at least some usage of SLAAC. And you're better off just not supporting ipv6 at all at that point

Re:IPv6 Is Hard by tremon on Monday February 17, 2025 @09:10AM (#43079170)
> they aren't the baseline expectation like it is with ipv6

Why not? Are you saying your computer doesn't need to know the IP address of any dns server in order to be useful?

What do you mean when you say that SLAAC is terrible? Especially when you control all the devices on the network, you are in full control of what SLAAC manages for you. Also, SLAAC is the only way to use the IPv6 Privacy Extensions.

Re:IPv6 Is Hard by kstrauser on Sunday February 16, 2025 @01:55PM (#43070548)
That's right. I'm specifically talking about mDNS, not DHCP+DNS. It works out of the box nearly all the time that I've tried it.
Re:IPv6 Is Hard by kllrnohj on Sunday February 16, 2025 @01:56PM (#43070553)
mDNS would work just fine but the given command ('ping foo') wouldn't be using mDNS. That's just standard name resolution. `ping foo.local` would potentially use mDNS if you have a ping that does such a thing, but that's restricted to `.local` specifically.

Rather, most routers add DHCP hostname requests to the local DNS routes. That doesn't require mDNS, nor would you want to replace it with mDNS as mDNS is more limited & flakier.

Re:IPv6 Is Hard by amaccuish on Sunday February 16, 2025 @02:08PM (#43070700)
My resolved in its default configuration will try appending .local and search via mDNS if no results are found via the DHCP provided server. I believe macOS does the same.

Ping foo on my machine results in foo.local being successfully pinged. Your mileage may vary.

> would potentially use mDNS if you have a ping that does such a thing

It's not a feature of ping, it's a feature of the name resolution setup on your machine (nsswitch and/or resolved on Linux).

> Rather, most routers add DHCP hostname requests to the local DNS routes

What do you mean?

Re:IPv6 Is Hard by vel0city on Sunday February 16, 2025 @02:39PM (#43070960)
You don't need DHCPv6 to auto register hosts in DNS. You just configure the DNS server to register based on neighbor discovery.

Things like RA and NDP would clue hosts into the local DNS server as well. You don't need DHCPv6 to advertise a local DNS server.