Tailscale allows to override the local DNS settings of a node via
"Override local DNS" [1]. Restore this flag with the same config setting
name `dns.override_local_dns` but disable it by default to align it with
Tailscale's default behaviour.
Tested with Tailscale 1.80.2 and systemd-resolved on Debian 12.
With `dns.override_local_dns: false`:
```
Link 12 (tailscale0)
Current Scopes: DNS
Protocols: -DefaultRoute -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
DNS Servers: 100.100.100.100
DNS Domain: tn.example.com ~0.e.1.a.c.5.1.1.a.7.d.f.ip6.arpa [snip]
```
With `dns.override_local_dns: true`:
```
Link 12 (tailscale0)
Current Scopes: DNS
Protocols: +DefaultRoute -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
DNS Servers: 100.100.100.100
DNS Domain: tn.example.com ~.
```
[1] https://tailscale.com/kb/1054/dns#override-local-dnsFixes: #2256
Upgrade the use of dns.use_username_in_magic_dns or
dns_config.use_username_in_magic_dns to a fatal error and remove the
option from the example configuration and integration tests.
Fixes: #2219
* config: loosen up BaseDomain and ServerURL checks
Requirements [here][1]:
> OK:
> server_url: headscale.com, base: clients.headscale.com
> server_url: headscale.com, base: headscale.net
>
> Not OK:
> server_url: server.headscale.com, base: headscale.com
>
> Essentially we have to prevent the possibility where the headscale
> server has a URL which can also be assigned to a node.
>
> So for the Not OK scenario:
>
> if the server is: server.headscale.com, and a node joins with the name
> server, it will be assigned server.headscale.com and that will break
> the connection for nodes which will now try to connect to that node
> instead of the headscale server.
Fixes#2210
[1]: https://github.com/juanfont/headscale/issues/2210#issuecomment-2488165187
* server_url and base_domain: re-word error message, fix a one-off bug and add a test case for the bug.
* lint
* lint again
this commit changes and streamlines the dns_config into a new
key, dns. It removes a combination of outdates and incompatible
configuration options that made it easy to confuse what headscale
could and could not do, or what to expect from ones configuration.
Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>
