nixpkgs/modules/config/networking.nix
Peter Simons 56373744b4 modules/config/networking.nix: recognize whether a local DNS resolver is available
resolvconf prefers a locally running BIND resolver over the forwarders; we just
have to tell it whether we have one or not. We use 'config.services.bind.enable'
to make that decision, assuming that people are not going to configure a local
BIND that won't respond to queries on 127.0.0.1. If we run into such a (weird)
case, then we'll need to introduce another variable for that purpose which can
be set independently from 'config.services.bind.enable'.
2012-07-02 15:01:02 +02:00

78 lines
2.1 KiB
Nix

# /etc files related to networking, such as /etc/services.
{config, pkgs, ...}:
with pkgs.lib;
let
cfg = config.networking;
options = {
networking.extraHosts = pkgs.lib.mkOption {
default = "";
example = "192.168.0.1 lanlocalhost";
description = ''
Additional entries to be appended to <filename>/etc/hosts</filename>.
'';
};
};
localhostWithDomain = optionalString (cfg.domain != "")
"localhost.${cfg.domain}";
hostnameWithDomain = optionalString
(cfg.domain != "" && cfg.hostName != "")
"${cfg.hostName}.${cfg.domain}";
in
{
require = [options];
environment.etc =
[ { # /etc/services: TCP/UDP port assignments.
source = pkgs.iana_etc + "/etc/services";
target = "services";
}
{ # /etc/protocols: IP protocol numbers.
source = pkgs.iana_etc + "/etc/protocols";
target = "protocols";
}
{ # /etc/rpc: RPC program numbers.
source = pkgs.glibc + "/etc/rpc";
target = "rpc";
}
{ # /etc/hosts: Hostname-to-IP mappings.
source = pkgs.writeText "hosts"
''
${optionalString (cfg.hostName != "")
"127.0.0.1 ${hostnameWithDomain} ${cfg.hostName}"}
127.0.0.1 localhost ${localhostWithDomain}
${cfg.extraHosts}
'';
target = "hosts";
}
{ # /etc/resolvconf.conf: Configuration for openresolv.
source = pkgs.writeText "resolvconf.conf" (
''
# This is the default, but we must set it here to prevent
# a collision with an apparently unrelated environment
# variable with the same name exported by dhcpcd.
interface_order='lo lo[0-9]*'
'' + optionalString config.services.nscd.enable ''
# Invalidate the nscd cache whenever resolv.conf is
# regenerated.
libc_restart='${pkgs.upstart}/sbin/start invalidate-nscd'
'' + optionalString config.services.bind.enable ''
# This hosts runs a full-blown DNS resolver.
name_servers='127.0.0.1'
'' );
target = "resolvconf.conf";
}
];
}