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Comment by zamadatix | Hacker News Reader

Why do you need split horizon DNS for that?

So if I ssh into another computer by it's name everything works without me having to maintain a static device table somewhere w/scripts to deal with inevitable versioning issues.

You don’t need split horizon dns as long as the router is running a resolver. Just configure the resolver to use some TLD (eg .local) as a local network so that it looks up any names ending in eg .local in its local /etc/hosts or equivalent.

.local isn't a recommendation any more due to zeroconf.

The "best way" is to use a real domain for your local network. But this can be annoying, costs money and has other issues (renaming/-branding, mergers/splits, domain squatting, accidental record publication and so on ---- it's a lot like renting an internet-routable IP network for LAN use, it's kinda silly and error prone).

What about .internal? https://tools.ietf.org/html/draft-wkumari-dnsop-internal-00

That draft has expired... so it's not official.

I just learned this however: https://www.icann.org/resources/board-material/resolutions-2...

So .corp and .home will not become gTLDs and should be relatively safe to use.

Ugh! It really is a situation of “we (ICANN) took money from people applying for these and don’t have the guts to officially say ‘no these are reserved for private usage, deal with it’ so we’ll call it ‘delay allocating these names indefinitely’”. At least they’re planning on refunding the applicants. And Google has the clout to push for making say .dev closed off via an RFC but instead bought it and runs it for their own (internal) development. It’s like no one has the concept of thinking about working for the public good for small groups or individuals on this modern internet. Tragedy of the commons.

Using non-private IP for your local network isn't "silly", it's just that we've grown accustomed to not doing so out of necessity. Reusing the same IP address for multiple hosts is problematic, even when there is an RFC that says it's okay to do so.

For instance, I've got a tinc VPN network setup between many of my hosts. What IP range should I set that to such that it will not clash with whatever access network my laptop roams onto? The proper IP-philosophy answer is to apply for a block, even if it's never announced by BGP.

The pragmatic hack is to attempt to choose the most obscure block that isn't likely to conflict with the public Internet or with how local networks are generally setup. In my case, I chose something NOT from RFC1918 (so shoot me).

It's of course less of a big deal if you do realm / split-horizon based routing. But that is not straightforward to setup, as it's getting away from how IP was designed to be used.

Internet-routable (v6) addresses on home LAN is a pretty standard thing and not silly at all. In many places you still get multiple v4 addresses too.

Like the other person said that's just a normal DNS lookup, not split horizon. Use one of the private TLDs like .test or .local.

I posted how to do split horizon above. I get it. You don't want to change your ssh config and doing things on lan instead of going through the router interfaces is ideal.

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