We do not really declare module dependencies anywhere else and it would
a nousance to move any file if many other referenced it without being
necessary. Also most higher level modules depend on most of the lower
level ones.
So removing this because it can only potentially cause weird issues.
It is now only about the system service.
Granted, it also installs the client package, but that could be
factored out later, with actual test to support such a new type of
configuration.
This makes it easier to for example set `datasource_list = [ "Vultr" ];`
so that cloud-init doesn't scan trough all of the datasources when you
know on which target the system is going to be deployed.
Previously, one had to copy-paste the default config and adapt it.
* cloud-init: 22.4 -> 23.1.1
* cloud-init: add udhcpc support
Cloud-init use as dhcp client, dhclient, which is coming from the unmaintained package, isc-dhcp-client (refer https://www.isc.org/dhcp/) which ended support in 2022. dhclient is deprecated in nixos
Add patch to use `udhcpc` dhcp client coming from busybox instead.
PR based on #226173
refs #215571
upstream PR: https://github.com/canonical/cloud-init/pull/2125
As announced in the NixOS 22.11 release notes, 23.05 will switch NixOS
to using nsncd (a non-caching reimplementation in Rust) as NSS lookup
dispatcher, instead of the buggy and deprecated glibc-provided nscd.
If you need to switch back, set `services.nscd.enableNsncd = false`, but
please open an issue in nixpkgs so your issue can be fixed.
- Do not use `daemon`, it has been synonymous to `out` since 783c40eb68
- Do not use explicit `out` output, it has been default since a17216af4c (originally introduced in 2132c86c45)
- Fix hostname configuration on proxmox, which uses "hostname" in user-data
instead of "local-hostname" in meta-data.
- Allow setting resolv.conf through cloud-init
- Add tests for new changes
- Add timeouts to make tests fail faster
conversions were done using https://github.com/pennae/nix-doc-munge
using (probably) rev f34e145 running
nix-doc-munge nixos/**/*.nix
nix-doc-munge --import nixos/**/*.nix
the tool ensures that only changes that could affect the generated
manual *but don't* are committed, other changes require manual review
and are discarded.
this mostly means marking options that use markdown already
appropriately and making a few adjustments so they still render
correctly. notable for nftables we have to transform the md links
because the manpage would not render them correctly otherwise.
This is to ensure the targets are stopped when nscd is stopped to
prevent races on switch. Example interaction: nscd is stopped, some
service that requires nss-user-lookup.target is restarted. Without this
PR, nss-user-lookup.target would still be active, hence the service
would start without nscd running.
we can't embed syntactic annotations of this kind in markdown code
blocks without yet another extension. replaceable is rare enough to make
this not much worth it, so we'll go with «thing» instead. the module
system already uses this format for its placeholder names in attrsOf
paths.
the conversion procedure is simple:
- find all things that look like options, ie calls to either `mkOption`
or `lib.mkOption` that take an attrset. remember the attrset as the
option
- for all options, find a `description` attribute who's value is not a
call to `mdDoc` or `lib.mdDoc`
- textually convert the entire value of the attribute to MD with a few
simple regexes (the set from mdize-module.sh)
- if the change produced a change in the manual output, discard
- if the change kept the manual unchanged, add some text to the
description to make sure we've actually found an option. if the
manual changes this time, keep the converted description
this procedure converts 80% of nixos options to markdown. around 2000
options remain to be inspected, but most of those fail the "does not
change the manual output check": currently the MD conversion process
does not faithfully convert docbook tags like <code> and <package>, so
any option using such tags will not be converted at all.
The NixOS evaluation would complain:
trace: warning: literalExample is deprecated, use literalExpression instead, or use literalDocBook for a non-Nix description.
* nixos/earlyoom: bring the module up to date
Removes deprecated option `ignoreOOMScoreAdjust`, introduces `killHook`
as a replacement for `notificationsCommand`, and adds an `extraArgs`
option for things not covered by the module.
* nixos/earlyoom: add nixos test
* nixos/earlyoom: add reportInterval
Allows setting the interval for logging a memory report. Defaults to
3600 following upstream
(https://github.com/rfjakob/earlyoom/blob/master/earlyoom.default#L5)
to avoid flooding logs.
* nixos/earlyoom: add free{Mem,Swap}KillThreshold
Fixes https://github.com/NixOS/nixpkgs/issues/83504
During working on #150837 I discovered that `google-oslogin` test
started failing, and so did some of my development machines. Turns out
it was because nscd doesn't start by default; rather it's wanted by
NSS lookup targets, which are not always fired up.
To quote from section on systemd.special(7) on `nss-user-lookup.target`:
> All services which provide parts of the user/group database should be
> ordered before this target, and pull it in.
Following this advice and comparing our unit to official `sssd.service`
unit (which is a similar service), we now pull NSS lookup targets from
the service, while starting it with `multi-user.target`.
This removes the `services.dbus.socketActivated` and
`services.xserver.startDbusSession` options. Instead the user D-Bus
session is always socket activated.
Since systemd 243, docs were already steering users towards using
`journal`:
eedaf7f322
systemd 246 will go one step further, it shows warnings for these units
during bootup, and will [automatically convert these occurences to
`journal`](f3dc6af20f):
> [ 6.955976] systemd[1]: /nix/store/hwyfgbwg804vmr92fxc1vkmqfq2k9s17-unit-display-manager.service/display-manager.service:27: Standard output type syslog is obsolete, automatically updating to journal. Please update│······················
your unit file, and consider removing the setting altogether.
So there's no point of keeping `syslog` here, and it's probably a better
idea to just not set it, due to:
> This setting defaults to the value set with DefaultStandardOutput= in
> systemd-system.conf(5), which defaults to journal.
This effectively disables nscd's built-in hosts cache, which turns out
to be erratic in some cases.
We only use nscd these days as a more ABI-neutral NSS dispatcher
mechanism.
Local caching should still be possible with local resolvers in
/etc/resolv.conf (via the `dns` NSS module), or without local resolvers
via systemd-networkd (via the `resolve` nss module)
We don't set enable-cache to no due to
https://github.com/NixOS/nixpkgs/pull/50316#discussion_r241035226.
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.
Since https://github.com/NixOS/nixpkgs/pull/61321, local-fs.target is
part of sysinit.target again, meaning units without
DefaultDependencies=no will automatically depend on it, and the manual
set dependencies can be dropped.
NixOS usually needs nscd just to have a single place where
LD_LIBRARY_PATH can be set to include all NSS modules, but nscd is also
useful if some of the NSS modules need to read files which are only
accessible by root.
For example, nixos/modules/config/ldap.nix needs this when
users.ldap.enable = true;
users.ldap.daemon.enable = false;
and users.ldap.bind.passwordFile exists. In that case, the module
creates an /etc/ldap.conf which is only readable by root, but which the
NSS module needs to read in order to find out what LDAP server to
connect to and with what credentials.
If nscd is started as root and configured with the server-user option in
nscd.conf, then it gives each NSS module the opportunity to initialize
itself before dropping privileges. The initialization happens in the
glibc-internal __nss_disable_nscd function, which pre-loads all the
configured NSS modules for passwd, group, hosts, and services (but not
netgroup for some reason?) and, for each loaded module, calls an init
function if one is defined. After that finishes, nscd's main() calls
nscd_init() which ends by calling finish_drop_privileges().
There are provisions in systemd for using DynamicUser with a service
which needs to drop privileges itself, so this patch does that.
Thanks to @arianvp for pointing out that when DynamicUser is true,
systemd defaults the value of User to be the name of the unit, which in
this case is already "nscd".
These options were being set to the same value as the defaults that are
hardcoded in nscd. Delete them so it's clear which settings are actually
important for NixOS.
One exception is `threads 1`, which is different from the built-in
default of 4. However, both values are equivalent because nscd forces
the number of threads to be at least as many as the number of kinds of
databases it supports, which is 5.
nscd doesn't create any files outside of /run/nscd unless the nscd.conf
"persistent" option is used, which we don't do by default. Therefore it
doesn't matter what UID/GID we run this service as, so long as it isn't
shared with any other running processes.
/run/nscd does need to be owned by the same UID that the service is
running as, but systemd takes care of that for us thanks to the
RuntimeDirectory directive.
If someone wants to turn on the "persistent" option, they need to
manually configure users.users.nscd and systemd.tmpfiles.rules so that
/var/db/nscd is owned by the same user that nscd runs as.
In an all-defaults boot.isContainer configuration of NixOS, this removes
the only user which did not have a pre-assigned UID.
Previously this module created both /var/db/nscd and /run/nscd using
shell commands in a preStart script. Note that both of these paths are
hard-coded in the nscd source. (Well, the latter is actually
/var/run/nscd but /var/run is a symlink to /run so it works out the
same.)
/var/db/nscd is only used if the nscd.conf "persistent" option is turned
on for one or more databases, which it is not in our default config
file. I'm not even sure persistent mode can work under systemd, since
`nscd --shutdown` is not synchronous so systemd will always
unceremoniously kill nscd without reliably giving it time to mark the
databases as unused. Nonetheless, if someone wants to use that option,
they can ensure the directory exists using systemd.tmpfiles.rules.
systemd can create /run/nscd for us with the RuntimeDirectory directive,
with the added benefit of causing systemd to delete the directory on
service stop or restart. The default value of RuntimeDirectoryMode is
755, the same as the mode which this module was using before.
I don't think the `rm -f /run/nscd/nscd.pid` was necessary after NixOS
switched to systemd and used its PIDFile directive, because systemd
deletes the specified file after the service stops, and because the file
can't persist across reboots since /run is a tmpfs. Even if the file
still exists when nscd starts, it's only a problem if the pid it
contains has been reused by another process, which is unlikely. Anyway,
this change makes that deletion even less necessary, because now systemd
deletes the entire /run/nscd directory when the service stops.
This postStart step was introduced on 2014-04-24 with the comment that
"Nscd forks into the background before it's ready to accept
connections."
However, that was fixed upstream almost two months earlier, on
2014-03-03, with the comment that "This, along with setting the nscd
service type to forking in its systemd configuration file, allows
systemd to be certain that the nscd service is ready and is accepting
connections."
The fix was released several months later in glibc 2.20, which was
merged in NixOS sometime before 15.09, so it certainly should be safe to
remove this workaround by now.
The geoclue module now lets us set application config. This should make
it more robust in environments that don't provide a geoclue agent.
Fixes#44725.
Systemd provides an option for allocating DynamicUsers
which we want to use in NixOS to harden service configuration.
However, we discovered that the user wasn't allocated properly
for services. After some digging this turned out to be, of course,
a cache inconsistency problem.
When a DynamicUser creation is performed, Systemd check beforehand
whether the requested user already exists statically. If it does,
it bails out. If it doesn't, systemd continues with allocating the
user.
However, by checking whether the user exists, nscd will store
the fact that the user does not exist in it's negative cache.
When the service tries to lookup what user is associated to its
uid (By calling whoami, for example), it will try to consult
libnss_systemd.so However this will read from the cache and tell
report that the user doesn't exist, and thus will return that
there is no user associated with the uid. It will continue
to do so for the cache duration time. If the service
doesn't immediately looks up its username, this bug is not
triggered, as the cache will be invalidated around this time.
However, if the service is quick enough, it might end up
in a situation where it's incorrectly reported that the
user doesn't exist.
Preferably, we would not be using nscd at all. But we need to
use it because glibc reads nss modules from /etc/nsswitch.conf
by looking relative to the global LD_LIBRARY_PATH. Because LD_LIBRARY_PATH
is not set globally (as that would lead to impurities and ABI issues),
glibc will fail to find any nss modules.
Instead, as a hack, we start up nscd with LD_LIBRARY_PATH set
for only that service. Glibc will forward all nss syscalls to
nscd, which will then respect the LD_LIBRARY_PATH and only
read from locations specified in the NixOS config.
we can load nss modules in a pure fashion.
However, I think by accident, we just copied over the default
settings of nscd, which actually caches user and group lookups.
We already disable this when sssd is enabled, as this interferes
with the correct working of libnss_sss.so as it already
does its own caching of LDAP requests.
(See https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/deployment_guide/usingnscd-sssd)
Because nscd caching is now also interferring with libnss_systemd.so
and probably also with other nsss modules, lets just pre-emptively
disable caching for now for all options related to users and groups,
but keep it for caching hosts ans services lookups.
Note that we can not just put in /etc/nscd.conf:
enable-cache passwd no
As this will actually cause glibc to _not_ forward the call to nscd
at all, and thus never reach the nss modules. Instead we set
the negative and positive cache ttls to 0 seconds as a workaround.
This way, Glibc will always forward requests to nscd, but results
will never be cached.
Fixes#50273
Could also move kdc.conf, but this makes it inconvenient to use command line
utilities with heimdal, as it would require specifying --config-file with every
command.
Allow switching out kerberos server implementation.
Sharing config is probably sensible, but implementation is different enough to
be worth splitting into two files. Not sure this is the correct way to split an
implementation, but it works for now.
Uses the switch from config.krb5 to select implementation.
Several service definitions used `mkEnableOption` with text starting
with "Whether to", which produced funny option descriptions like
"Whether to enable Whether to run the rspamd daemon..".
This commit corrects this, and adds short descriptions of services
to affected service definitions.
Some modules of cloud-init can cope with a network not immediately
available (notably, the EC2 module), but some others won't retry if
network is not available (notably, the Cloudstack module).
network.target doesn't give much guarantee about the network
availability. Applications not able to start without a fully
configured network should be ordered after network-online.target.
Also see #44573 and #44524.
DBus seems to resolve user IDs directly via glibc, circumventing nscd. In more
advanced setups this leads to user's coming from LDAP or SSSD not being
resolved by the dbus system bus daemon. The effect for such users is, that all
access to the system bus (e.g. busctl or nmcli) is denied.
Adding the respective NSS modules to the service's environment solves the issue
the same way it does for nscd.
