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Comment by drdaeman | Hacker News Reader

> with resolved you cannot connect to other machines on your local network by specifying their simple names

Huh? You most certainly can. I mean, somehow "ssh koyomi" works here on my network, no matter if machine I run this on uses system-resolved or unbound or something else. My DHCP server supplies options 119 and 135 and that's all that's necessary to make it work.

What you can't is to have a CNAME with a bare hostname i.e. make "foo.example.org" magically resolve to "foo.local" when you're on that particular LAN with "search local" (and $deity knows what if you're not). To be honest, I'm not even sure what's the point of this setup, unless you do split-horizon (but then why not respond with "foo.local." proper?)

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Do you have a proper domain name for your local network (+ search domain)? I'm talking about the case where you don't, or have a '.local' domain; https://askubuntu.com/a/918161

Oh, now I get it. Sorry, it was not obvious from the bug you've linked above - there it talked about a CNAME record referencing a bare hostname from a "proper" (non-mDNS) domain name, a fairly weird use case I don't quite get.

Yes, I do have a "proper" domain name for my LAN and my .local is for mDNS (although I don't think I've ever used it with short names, always foo.local explicit; and I use mDNS very infrequently) - guess which is why I haven't ever seen this behavior. Thank you for clarifying.

The .local name is intended for multicast name resolution. RFC6762 says implementations may coalesce results with unicast DNS lookups, but it's not required. The only thing required is that anything ending in .local must he looked up via mDNS. So including .local in the search list doesn't seem likely to make your query reach DNS on an mDNS capable stub resolver.

Meanwhile, RFC4795 says that LLMNR senders should not send queries for single-label domains to DNS and that no search list should be applied to such. So querying a single-label domain does not seem likely to reach DNS on an LLMNR capable stub resolver.

My advice to one who wants to use DNS to resolve hostnames on the local network: Avoid using a domain reserved for mDNS domain and use another one.

The thing is that a simple name doesn't work either, so 'server1' doesn't work, 'server1.local' doesn't work. 'server1.example.com' works, and I think 'server1.lan' also works, but I'm not sure about that last one.

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