summary refs log tree commit diff
path: root/nixos/modules/services/monitoring/nagios.nix
blob: 9ac6869068f2baa09050bc01649e038de24f03c6 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
# Nagios system/network monitoring daemon.
{ config, lib, pkgs, ... }:

with lib;

let
  cfg = config.services.nagios;

  nagiosState = "/var/lib/nagios";
  nagiosLogDir = "/var/log/nagios";
  urlPath = "/nagios";

  nagiosObjectDefs = cfg.objectDefs;

  nagiosObjectDefsDir = pkgs.runCommand "nagios-objects" {
      inherit nagiosObjectDefs;
      preferLocalBuild = true;
    } "mkdir -p $out; ln -s $nagiosObjectDefs $out/";

  nagiosCfgFile = let
    default = {
      log_file="${nagiosLogDir}/current";
      log_archive_path="${nagiosLogDir}/archive";
      status_file="${nagiosState}/status.dat";
      object_cache_file="${nagiosState}/objects.cache";
      temp_file="${nagiosState}/nagios.tmp";
      lock_file="/run/nagios.lock";
      state_retention_file="${nagiosState}/retention.dat";
      query_socket="${nagiosState}/nagios.qh";
      check_result_path="${nagiosState}";
      command_file="${nagiosState}/nagios.cmd";
      cfg_dir="${nagiosObjectDefsDir}";
      nagios_user="nagios";
      nagios_group="nagios";
      illegal_macro_output_chars="`~$&|'\"<>";
      retain_state_information="1";
    };
    lines = mapAttrsToList (key: value: "${key}=${value}") (default // cfg.extraConfig);
    content = concatStringsSep "\n" lines;
    file = pkgs.writeText "nagios.cfg" content;
    validated =  pkgs.runCommand "nagios-checked.cfg" {preferLocalBuild=true;} ''
      cp ${file} nagios.cfg
      # nagios checks the existence of /var/lib/nagios, but
      # it does not exists in the build sandbox, so we fake it
      mkdir lib
      lib=$(readlink -f lib)
      sed -i s@=${nagiosState}@=$lib@ nagios.cfg
      ${pkgs.nagios}/bin/nagios -v nagios.cfg && cp ${file} $out
    '';
    defaultCfgFile = if cfg.validateConfig then validated else file;
  in
  if cfg.mainConfigFile == null then defaultCfgFile else cfg.mainConfigFile;

  # Plain configuration for the Nagios web-interface with no
  # authentication.
  nagiosCGICfgFile = pkgs.writeText "nagios.cgi.conf"
    ''
      main_config_file=${cfg.mainConfigFile}
      use_authentication=0
      url_html_path=${urlPath}
    '';

  extraHttpdConfig =
    ''
      ScriptAlias ${urlPath}/cgi-bin ${pkgs.nagios}/sbin

      <Directory "${pkgs.nagios}/sbin">
        Options ExecCGI
        Require all granted
        SetEnv NAGIOS_CGI_CONFIG ${cfg.cgiConfigFile}
      </Directory>

      Alias ${urlPath} ${pkgs.nagios}/share

      <Directory "${pkgs.nagios}/share">
        Options None
        Require all granted
      </Directory>
    '';

in
{
  imports = [
    (mkRemovedOptionModule [ "services" "nagios" "urlPath" ] "The urlPath option has been removed as it is hard coded to /nagios in the nagios package.")
  ];

  meta.maintainers = with lib.maintainers; [ symphorien ];

  options = {
    services.nagios = {
      enable = mkEnableOption "<link xlink:href='http://www.nagios.org/'>Nagios</link> to monitor your system or network.";

      objectDefs = mkOption {
        description = "
          A list of Nagios object configuration files that must define
          the hosts, host groups, services and contacts for the
          network that you want Nagios to monitor.
        ";
        type = types.listOf types.path;
        example = literalExample "[ ./objects.cfg ]";
      };

      plugins = mkOption {
        type = types.listOf types.package;
        default = with pkgs; [ nagiosPluginsOfficial ssmtp mailutils ];
        defaultText = "[pkgs.nagiosPluginsOfficial pkgs.ssmtp pkgs.mailutils]";
        description = "
          Packages to be added to the Nagios <envar>PATH</envar>.
          Typically used to add plugins, but can be anything.
        ";
      };

      mainConfigFile = mkOption {
        type = types.nullOr types.package;
        default = null;
        description = "
          If non-null, overrides the main configuration file of Nagios.
        ";
      };

      extraConfig = mkOption {
        type = types.attrsOf types.str;
        example = {
          debug_level = "-1";
          debug_file = "/var/log/nagios/debug.log";
        };
        default = {};
        description = "Configuration to add to /etc/nagios.cfg";
      };

      validateConfig = mkOption {
        type = types.bool;
        default = pkgs.stdenv.hostPlatform == pkgs.stdenv.buildPlatform;
        description = "if true, the syntax of the nagios configuration file is checked at build time";
      };

      cgiConfigFile = mkOption {
        type = types.package;
        default = nagiosCGICfgFile;
        defaultText = "nagiosCGICfgFile";
        description = "
          Derivation for the configuration file of Nagios CGI scripts
          that can be used in web servers for running the Nagios web interface.
        ";
      };

      enableWebInterface = mkOption {
        type = types.bool;
        default = false;
        description = "
          Whether to enable the Nagios web interface.  You should also
          enable Apache (<option>services.httpd.enable</option>).
        ";
      };

      virtualHost = mkOption {
        type = types.submodule (import ../web-servers/apache-httpd/vhost-options.nix);
        example = literalExample ''
          { hostName = "example.org";
            adminAddr = "webmaster@example.org";
            enableSSL = true;
            sslServerCert = "/var/lib/acme/example.org/full.pem";
            sslServerKey = "/var/lib/acme/example.org/key.pem";
          }
        '';
        description = ''
          Apache configuration can be done by adapting <option>services.httpd.virtualHosts</option>.
          See <xref linkend="opt-services.httpd.virtualHosts"/> for further information.
        '';
      };
    };
  };


  config = mkIf cfg.enable {
    users.users.nagios = {
      description = "Nagios user ";
      uid         = config.ids.uids.nagios;
      home        = nagiosState;
      group       = "nagios";
    };

    users.groups.nagios = { };

    # This isn't needed, it's just so that the user can type "nagiostats
    # -c /etc/nagios.cfg".
    environment.etc."nagios.cfg".source = nagiosCfgFile;

    environment.systemPackages = [ pkgs.nagios ];
    systemd.services.nagios = {
      description = "Nagios monitoring daemon";
      path     = [ pkgs.nagios ] ++ cfg.plugins;
      wantedBy = [ "multi-user.target" ];
      after    = [ "network.target" ];

      serviceConfig = {
        User = "nagios";
        Group = "nagios";
        Restart = "always";
        RestartSec = 2;
        LogsDirectory = "nagios";
        StateDirectory = "nagios";
        ExecStart = "${pkgs.nagios}/bin/nagios /etc/nagios.cfg";
        X-ReloadIfChanged = nagiosCfgFile;
      };
    };

    services.httpd.virtualHosts = optionalAttrs cfg.enableWebInterface {
      ${cfg.virtualHost.hostName} = mkMerge [ cfg.virtualHost { extraConfig = extraHttpdConfig; } ];
    };
  };
}