README.txt 16 KB

  1. NSSM: The Non-Sucking Service Manager
  2. Version 2.21, 2013-11-24
  3. NSSM is a service helper program similar to srvany and cygrunsrv. It can
  4. start any application as an NT service and will restart the service if it
  5. fails for any reason.
  6. NSSM also has a graphical service installer and remover.
  7. Full documentation can be found online at
  9. Since version 2.0, the GUI can be bypassed by entering all appropriate
  10. options on the command line.
  11. Since version 2.1, NSSM can be compiled for x64 platforms.
  12. Thanks Benjamin Mayrargue.
  13. Since version 2.2, NSSM can be configured to take different actions
  14. based on the exit code of the managed application.
  15. Since version 2.3, NSSM logs to the Windows event log more elegantly.
  16. Since version 2.5, NSSM respects environment variables in its parameters.
  17. Since version 2.8, NSSM tries harder to shut down the managed application
  18. gracefully and throttles restart attempts if the application doesn't run
  19. for a minimum amount of time.
  20. Since version 2.11, NSSM respects srvany's AppEnvironment parameter.
  21. Since version 2.13, NSSM is translated into French.
  22. Thanks François-Régis Tardy.
  23. Since version 2.15, NSSM is translated into Italian.
  24. Thanks Riccardo Gusmeroli.
  25. Since version 2.17, NSSM can try to shut down console applications by
  26. simulating a Control-C keypress. If they have installed a handler routine
  27. they can clean up and shut down gracefully on receipt of the event.
  28. Since version 2.17, NSSM can redirect the managed application's I/O streams
  29. to an arbitrary path.
  30. Since version 2.18, NSSM can be configured to wait a user-specified amount
  31. of time for the application to exit when shutting down.
  32. Since version 2.19, many more service options can be configured with the
  33. GUI installer as well as via the registry.
  34. Since version 2.19, NSSM can add to the service's environment by setting
  35. AppEnvironmentExtra in place of or in addition to the srvany-compatible
  36. AppEnvironment.
  37. Since version 2.22, NSSM can rotate existing output files when redirecting I/O.
  38. Since version 2.22, NSSM can set service display name, description, startup
  39. type and log on details.
  40. Since version 2.22, NSSM can edit existing services with the GUI.
  41. Usage
  42. -----
  43. In the usage notes below, arguments to the program may be written in angle
  44. brackets and/or square brackets. <string> means you must insert the
  45. appropriate string and [<string>] means the string is optional. See the
  46. examples below...
  47. Installation using the GUI
  48. --------------------------
  49. To install a service, run
  50. nssm install <servicename>
  51. You will be prompted to enter the full path to the application you wish
  52. to run and any command line options to pass to that application.
  53. Use the system service manager (services.msc) to control advanced service
  54. properties such as startup method and desktop interaction. NSSM may
  55. support these options at a later time...
  56. Installation using the command line
  57. -----------------------------------
  58. To install a service, run
  59. nssm install <servicename> <application> [<options>]
  60. NSSM will then attempt to install a service which runs the named application
  61. with the given options (if you specified any).
  62. Don't forget to enclose paths in "quotes" if they contain spaces!
  63. If you want to include quotes in the options you will need to """quote""" the
  65. Managing the service
  66. --------------------
  67. NSSM will launch the application listed in the registry when you send it a
  68. start signal and will terminate it when you send a stop signal. So far, so
  69. much like srvany. But NSSM is the Non-Sucking service manager and can take
  70. action if/when the application dies.
  71. With no configuration from you, NSSM will try to restart itself if it notices
  72. that the application died but you didn't send it a stop signal. NSSM will
  73. keep trying, pausing between each attempt, until the service is successfully
  74. started or you send it a stop signal.
  75. NSSM will pause an increasingly longer time between subsequent restart attempts
  76. if the service fails to start in a timely manner, up to a maximum of four
  77. minutes. This is so it does not consume an excessive amount of CPU time trying
  78. to start a failed application over and over again. If you identify the cause
  79. of the failure and don't want to wait you can use the Windows service console
  80. (where the service will be shown in Paused state) to send a continue signal to
  81. NSSM and it will retry within a few seconds.
  82. By default, NSSM defines "a timely manner" to be within 1500 milliseconds.
  83. You can change the threshold for the service by setting the number of
  84. milliseconds as a REG_DWORD value in the registry at
  85. HKLM\SYSTEM\CurrentControlSet\Services\<service>\Parameters\AppThrottle.
  86. NSSM will look in the registry under
  87. HKLM\SYSTEM\CurrentControlSet\Services\<service>\Parameters\AppExit for
  88. string (REG_EXPAND_SZ) values corresponding to the exit code of the application.
  89. If the application exited with code 1, for instance, NSSM will look for a
  90. string value under AppExit called "1" or, if it does not find it, will
  91. fall back to the AppExit (Default) value. You can find out the exit code
  92. for the application by consulting the system event log. NSSM will log the
  93. exit code when the application exits.
  94. Based on the data found in the registry, NSSM will take one of three actions:
  95. If the value data is "Restart" NSSM will try to restart the application as
  96. described above. This is its default behaviour.
  97. If the value data is "Ignore" NSSM will not try to restart the application
  98. but will continue running itself. This emulates the (usually undesirable)
  99. behaviour of srvany. The Windows Services console would show the service
  100. as still running even though the application has exited.
  101. If the value data is "Exit" NSSM will exit gracefully. The Windows Services
  102. console would show the service as stopped. If you wish to provide
  103. finer-grained control over service recovery you should use this code and
  104. edit the failure action manually. Please note that Windows versions prior
  105. to Vista will not consider such an exit to be a failure. On older versions
  106. of Windows you should use "Suicide" instead.
  107. If the value data is "Suicide" NSSM will simulate a crash and exit without
  108. informing the service manager. This option should only be used for
  109. pre-Vista systems where you wish to apply a service recovery action. Note
  110. that if the monitored application exits with code 0, NSSM will only honour a
  111. request to suicide if you explicitly configure a registry key for exit code 0.
  112. If only the default action is set to Suicide NSSM will instead exit gracefully.
  113. Stopping the service
  114. --------------------
  115. When stopping a service NSSM will attempt several different methods of killing
  116. the monitored application, each of which can be disabled if necessary.
  117. First NSSM will attempt to generate a Control-C event and send it to the
  118. application's console. Batch scripts or console applications may intercept
  119. the event and shut themselves down gracefully. GUI applications do not have
  120. consoles and will not respond to this method.
  121. Secondly NSSM will enumerate all windows created by the application and send
  122. them a WM_CLOSE message, requesting a graceful exit.
  123. Thirdly NSSM will enumerate all threads created by the application and send
  124. them a WM_QUIT message, requesting a graceful exit. Not all applications'
  125. threads have message queues; those which do not will not respond to this
  126. method.
  127. Finally NSSM will call TerminateProcess() to request that the operating
  128. system forcibly terminate the application. TerminateProcess() cannot be
  129. trapped or ignored, so in most circumstances the application will be killed.
  130. However, there is no guarantee that it will have a chance to perform any
  131. tidyup operations before it exits.
  132. Any or all of the methods above may be disabled. NSSM will look for the
  133. HKLM\SYSTEM\CurrentControlSet\Services\<service>\Parameters\AppStopMethodSkip
  134. registry value which should be of type REG_DWORD set to a bit field describing
  135. which methods should not be applied.
  136. If AppStopMethodSkip includes 1, Control-C events will not be generated.
  137. If AppStopMethodSkip includes 2, WM_CLOSE messages will not be posted.
  138. If AppStopMethodSkip includes 4, WM_QUIT messages will not be posted.
  139. If AppStopMethodSkip includes 8, TerminateProcess() will not be called.
  140. If, for example, you knew that an application did not respond to Control-C
  141. events and did not have a thread message queue, you could set AppStopMethodSkip
  142. to 5 and NSSM would not attempt to use those methods to stop the application.
  143. Take great care when including 8 in the value of AppStopMethodSkip. If NSSM
  144. does not call TerminateProcess() it is possible that the application will not
  145. exit when the service stops.
  146. By default NSSM will allow processes 1500ms to respond to each of the methods
  147. described above before proceeding to the next one. The timeout can be
  148. configured on a per-method basis by creating REG_DWORD entries in the
  149. registry under HKLM\SYSTEM\CurrentControlSet\Services\<service>\Parameters.
  150. AppStopMethodConsole
  151. AppStopMethodWindow
  152. AppStopMethodThreads
  153. Each value should be set to the number of milliseconds to wait. Please note
  154. that the timeout applies to each process in the application's process tree,
  155. so the actual time to shutdown may be longer than the sum of all configured
  156. timeouts if the application spawns multiple subprocesses.
  157. I/O redirection
  158. ---------------
  159. NSSM can redirect the managed application's I/O to any path capable of being
  160. opened by CreateFile(). This enables, for example, capturing the log output
  161. of an application which would otherwise only write to the console or accepting
  162. input from a serial port.
  163. NSSM will look in the registry under
  164. HKLM\SYSTEM\CurrentControlSet\Services\<service>\Parameters for the keys
  165. corresponding to arguments to CreateFile(). All are optional. If no path is
  166. given for a particular stream it will not be redirected. If a path is given
  167. but any of the other values are omitted they will be receive sensible defaults.
  168. AppStdin: Path to receive input.
  169. AppStdout: Path to receive output.
  170. AppStderr: Path to receive error output.
  171. Parameters for CreateFile() are providing with the "AppStdinShareMode",
  172. "AppStdinCreationDisposition" and "AppStdinFlagsAndAttributes" values (and
  173. analogously for stdout and stderr).
  174. In general, if you want the service to log its output, set AppStdout and
  175. AppStderr to the same path, eg C:\Users\Public\service.log, and it should
  176. work. Remember, however, that the path must be accessible to the user
  177. running the service.
  178. File rotation
  179. -------------
  180. When using I/O redirection, NSSM can rotate existing output files prior to
  181. opening stdout and/or stderr. An existing file will be renamed with a
  182. suffix based on the file's last write time, to millisecond precision. For
  183. example, the file nssm.log might be rotated to nssm-20131221T113939.457.log.
  184. NSSM will look in the registry under
  185. HKLM\SYSTEM\CurrentControlSet\Services\<service>\Parameters for REG_DWORD
  186. entries which control how rotation happens.
  187. If AppRotateFiles is missing or set to 0, rotation is disabled. Any non-zero
  188. value enables rotation.
  189. If AppRotateSeconds is non-zero, a file will not be rotated if its last write
  190. time is less than the given number of seconds in the past.
  191. If AppRotateBytes is non-zero, a file will not be rotated if it is smaller
  192. than the given number of bytes. 64-bit file sizes can be handled by setting
  193. a non-zero value of AppRotateBytesHigh.
  194. Rotation is independent of the CreateFile() parameters used to open the files.
  195. They will be rotated regardless of whether NSSM would otherwise have appended
  196. or replaced them.
  197. Environment variables
  198. ---------------------
  199. NSSM can replace or append to the managed application's environment. Two
  200. multi-valued string (REG_MULTI_SZ) registry values are recognised under
  201. HKLM\SYSTEM\CurrentControlSet\Services\<service>\Parameters.
  202. AppEnvironment defines a list of environment variables which will override
  203. the service's environment. AppEnvironmentExtra defines a list of
  204. environment variables which will be added to the service's environment.
  205. Each entry in the list should be of the form KEY=VALUE. It is possible to
  206. omit the VALUE but the = symbol is mandatory.
  207. srvany only supports AppEnvironment.
  208. Managing services using the GUI
  209. -------------------------------
  210. NSSM can edit the settings of existing services with the same GUI that is
  211. used to install them. Run
  212. nssm edit <servicename>
  213. to bring up the GUI.
  214. NSSM offers limited editing capabilities for services other than those which
  215. run NSSM itself. When NSSM is asked to edit a service which does not have
  216. the App* registry settings described above, the GUI will allow editing only
  217. system settings such as the service display name and description.
  218. Removing services using the GUI
  219. -------------------------------
  220. NSSM can also remove services. Run
  221. nssm remove <servicename>
  222. to remove a service. You will prompted for confirmation before the service
  223. is removed. Try not to remove essential system services...
  224. Removing service using the command line
  225. ---------------------------------------
  226. To remove a service without confirmation from the GUI, run
  227. nssm remove <servicename> confirm
  228. Try not to remove essential system services...
  229. Logging
  230. -------
  231. NSSM logs to the Windows event log. It registers itself as an event log source
  232. and uses unique event IDs for each type of message it logs. New versions may
  233. add event types but existing event IDs will never be changed.
  234. Because of the way NSSM registers itself you should be aware that you may not
  235. be able to replace the NSSM binary if you have the event viewer open and that
  236. running multiple instances of NSSM from different locations may be confusing if
  237. they are not all the same version.
  238. Example usage
  239. -------------
  240. To install an Unreal Tournament server:
  241. nssm install UT2004 c:\games\ut2004\system\ucc.exe server
  242. To remove the server:
  243. nssm remove UT2004 confirm
  244. Building NSSM from source
  245. -------------------------
  246. NSSM is known to compile with Visual Studio 2008. Older Visual Studio
  247. releases may or may not work.
  248. NSSM will also compile with Visual Studio 2010 but the resulting executable
  249. will not run on versions of Windows older than XP SP2. If you require
  250. compatiblity with older Windows releases you should change the Platform
  251. Toolset to v90 in the General section of the project's Configuration
  252. Properties.
  253. Credits
  254. -------
  255. Thanks to Bernard Loh for finding a bug with service recovery.
  256. Thanks to Benjamin Mayrargue ( for adding 64-bit support.
  257. Thanks to Joel Reingold for spotting a command line truncation bug.
  258. Thanks to Arve Knudsen for spotting that child processes of the monitored
  259. application could be left running on service shutdown, and that a missing
  260. registry value for AppDirectory confused NSSM.
  261. Thanks to Peter Wagemans and Laszlo Keresztfalvi for suggesting throttling restarts.
  262. Thanks to Eugene Lifshitz for finding an edge case in CreateProcess() and for
  263. advising how to build correctly in paths containing spaces.
  264. Thanks to Rob Sharp for pointing out that NSSM did not respect the
  265. AppEnvironment registry value used by srvany.
  266. Thanks to Szymon Nowak for help with Windows 2000 compatibility.
  267. Thanks to François-Régis Tardy for French translation.
  268. Thanks to Emilio Frini for spotting that French was inadvertently set as
  269. the default language when the user's display language was not translated.
  270. Thanks to Riccardo Gusmeroli for Italian translation.
  271. Thanks to Eric Cheldelin for the inspiration to generate a Control-C event
  272. on shutdown.
  273. Thanks to Brian Baxter for suggesting how to escape quotes from the command prompt.
  274. Thanks to Russ Holmann for suggesting that the shutdown timeout be configurable.
  275. Thanks to Paul Spause for spotting a bug with default registry entries.
  276. Thanks to BUGHUNTER for spotting more GUI bugs.
  277. Thanks to Doug Watson for suggesting file rotation.
  278. Licence
  279. -------
  280. NSSM is public domain. You may unconditionally use it and/or its source code
  281. for any purpose you wish.