PM2 is “…a production process manager for Node.js applications with a built-in load balancer. It allows you to keep applications alive forever, to reload them without downtime and to facilitate common system admin tasks…”.

I use PM2 to run and monitor Express apps. Below is a quick list of steps I follow to install PM2 (version 4.2.3 at time of writing) on Windows and run as a Windows service, tested on Windows Server 2016.

Implied is my “works for me” disclaimer at the bottom of this post - these steps are not the only or best way to install PM2 on Windows, but work for me and might hopefully be useful to someone else :-)

1. create a local administrator on the Windows server e.g. PM2Admin

2. log in as the local administrator (all the steps below are performed as as the local administrator created in step 1 unless specified)

   • why? as at early 2020, installing globally using npm saves to a user’s profile. I’ve found it best to log in as that specific user to perform all PM2 actions.

3. if not already done, install Node.js

4. from a command prompt (may need to be an administrative command prompt depending on how the Windows server is set up), install PM2 globally as per https://pm2.io/doc/en/runtime/guide/installation: npm install -g pm2

5. create a PM2 directory, for example C:\pm2

6. create an environment variable “PM2_HOME” pointing at directory created in step 5 (e.g. C:\pm2) as per https://blog.cloudboost.io/nodejs-pm2-startup-on-windows-db0906328d75

7. restart the server, log in again as the local administrator created in step 1

8. test PM2 by running pm2 save from a command prompt before installing the Windows service below

9. as per https://blog.cloudboost.io/nodejs-pm2-startup-on-windows-db0906328d75, from a command prompt, install pm2-windows-service globally: npm install -g pm2-windows-service

10. if there’s issues installing or running pm2-windows-service, may need to update old dependency as per https://github.com/jon-hall/pm2-windows-service/issues/51#issuecomment-532066926

11. from a command prompt, run pm2-service-install -n PM2, and answer questions as below:

    ? Perform environment setup (recommended)? Yes
    ? Set PM2_HOME? Yes
    ? PM2_HOME value (this path should be accessible to the service user and should not contain any “user-context” variables [e.g. %APPDATA%]): C:\pm2
    ? Set PM2_SERVICE_SCRIPTS (the list of start-up scripts for pm2)? No
    ? Set PM2_SERVICE_PM2_DIR (the location of the global pm2 to use with the service)? [recommended] Yes
    ? Specify the directory containing the pm2 version to be used by the service C:\USERS\<USER>\APPDATA\ROAMING\NPM\node_modules\pm2\index.js
    

12. a Windows service called “PM2” should now be configured and can be managed & started using Services Manager

13. reminder: files in the C:\pm2 directory should not be edited

14. (optional) can install PM2 log rotate module from a command prompt (see https://github.com/keymetrics/pm2-logrotate for more info): pm2 install pm2-logrotate

15. may need a process to clean up PM2 log rotate logs themselves, such as the following PowerShell snippet:

Get-ChildItem -Path 'C:\pm2\logs\*' -Include 'pm2-logrotate-out__*.log' | Where-Object { $_.LastWriteTime -lt (Get-Date).AddMonths(-1) } | Remove-Item