This fixes the output of "hostname --fqdn" (previously the domain name
was not appended). Additionally it's now possible to use the FQDN.
This works by unconditionally adding two entries to /etc/hosts:
127.0.0.1 localhost
::1 localhost
These are the first two entries and therefore gethostbyaddr() will
always resolve "127.0.0.1" and "::1" back to "localhost" [0].
This works because nscd (or rather the nss-files module) returns the
first matching row from /etc/hosts (and ignores the rest).
The FQDN and hostname entries are appended later to /etc/hosts, e.g.:
127.0.0.2 nixos-unstable.test.tld nixos-unstable
::1 nixos-unstable.test.tld nixos-unstable
Note: We use 127.0.0.2 here to follow nss-myhostname (systemd) as close
as possible. This has the advantage that 127.0.0.2 can be resolved back
to the FQDN but also the drawback that applications that only listen to
127.0.0.1 (and not additionally ::1) cannot be reached via the FQDN.
If you would like this to work you can use the following configuration:
```nix
networking.hosts."127.0.0.1" = [
"${config.networking.hostName}.${config.networking.domain}"
config.networking.hostName
];
```
Therefore gethostbyname() resolves "nixos-unstable" to the FQDN
(canonical name): "nixos-unstable.test.tld".
Advantages over the previous behaviour:
- The FQDN will now also be resolved correctly (the entry was missing).
- E.g. the command "hostname --fqdn" will now work as expected.
Drawbacks:
- Overrides entries form the DNS (an issue if e.g. $FQDN should resolve
to the public IP address instead of 127.0.0.1)
- Note: This was already partly an issue as there's an entry for
$HOSTNAME (without the domain part) that resolves to
127.0.1.1 (!= 127.0.0.1).
- Unknown (could potentially cause other unexpected issues, but special
care was taken).
[0]: Some applications do apparently depend on this behaviour (see
c578924) and this is typically the expected behaviour.
Co-authored-by: Florian Klink <flokli@flokli.de>
This prevents duplication in cross-compiled nixos machines. The
bootstrapped glibc differs from the natively compiled one, so we get
two glibc’s in the closure. To reduce closure size, just use
stdenv.cc.libc where available.
When blocklists are built with a derivation, using extraHosts would
require IFD, since the result of the derivation needs to be converted to
a string again.
By introducing this option no IFD is needed for such use-cases, since
the fetched files can be assigned directly.
A centralized list for these renames is not good because:
- It breaks disabledModules for modules that have a rename defined
- Adding/removing renames for a module means having to find them in the
central file
- Merge conflicts due to multiple people editing the central file
This PR is part of the networking.* namespace cleanup. We feel that
networking.hostConf is rarely used and provides little value compared to
using environment.etc."host.conf" directly.
Provide sensible default: multi on
This is a refactor of how resolvconf is managed on NixOS. We split it
into a separate service which is enabled internally depending on whether
we want /etc/resolv.conf to be managed by it. Various services now take
advantage of those configuration options.
We also now use systemd instead of activation scripts to update
resolv.conf.
NetworkManager now uses the right option for rc-manager DNS
automatically, so the configuration option shouldn't be exposed.
Add an option to set the rc-manager parameter in NetworkManager.conf,
which controls how NetworkManager handles resolv.conf. This sets the
default rc-manager to "resolvconf", which solves #61490. It
additionally allows the user to change rc-manager without interference
from configuration activations.
We use `127.0.1.1` instead of `127.0.0.1` because some applications will fail if
`127.0.0.1` resolves to something other than `localhost`.
Debian does the same.
See #1248 and #36261.
Since `networking.hosts` is properly typed all of that magic `/etc/hosts` generator
does can be dropped. People that disagree with the value of `networking.hosts` can
simply `mkForce`.
Forcibly restarting NSCD is unnecessary and breaks setups that use SSSD for
authentication. NSCD is capable of detecting changes to /etc/resolv.conf and
invalidating its caches internally. Restarting NSCD/SSSD breaks user name and
UID resolution.
This reverts commit 670b4e29ad. The change
added in this commit was controversial when it was originally suggested
in https://github.com/NixOS/nixpkgs/pull/29205. Then that PR was closed
and a new one opened, https://github.com/NixOS/nixpkgs/pull/29503,
effectively circumventing the review process. I don't agree with this
modification. Adding an option 'resolveLocalQueries' to tell the locally
running name server that it should resolve local DNS queries feels
outright nuts. I agree that the current state is unsatisfactory and that
it should be improved, but this is not the right way.
(cherry picked from commit 23a021d12e)
When the user specifies the networking.nameservers setting in the
configuration file, it must take precedence over automatically
derived settings.
The culprit was services.bind that made the resolver set to
127.0.0.1 and ignore the nameserver setting.
This patch adds a flag to services.bind to override the nameserver
to localhost. It defaults to true. Setting this to false prevents the
service.bind and dnsmasq.resolveLocalQueries settings from
overriding the users' settings.
Also, when the user specifies a domain to search, it must be set in
the resolver configuration, even if the user does not specify any
nameservers.
(cherry picked from commit 670b4e29ad)
This commit was accidentally merged to 17.09 but was intended for
master. This is the cherry-pick to master.
- most nixos user only require time synchronisation,
while ntpd implements a battery-included ntp server (1,215 LOCs of C-Code vs 64,302)
- timesyncd support ntp server per interface (if configured through dhcp for instance)
- timesyncd is already included in the systemd package, switching to it would
save a little disk space (1,5M)
Using "tmpfs" as a script part for system.activationScripts is a bit
misleading since 6efcfe03ae.
We no longer solely mount tmpfs within this script, so using "specialfs"
fits more nicely in terms of naming.
Tested against the "simple" NixOS installer test.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
Systemd upstream provides targets for networking. This also includes a target network-online.target.
In this PR I remove / replace most occurrences since some of them were even wrong and could delay startup.
Set this option to 'true' (default: 'false') to enable extension mechanisms for
DNS (EDNS) in your local glibc resolver. This is required for supporting
DNSSEC, for example.
Implementation detail: the patch changes assignments to "resolv_conf_options"
to use "+=" instead of "=" to ensure that multiple users of that variable don't
overwrite each other. The generated config file is a shell script, after all,
so this should work fine.
Closes https://github.com/NixOS/nixpkgs/issues/12470.
