pm2-installer

pm2-installer is designed to automate installation of pm2 as a service, particularly on Windows, even in environments without Internet access.

Windows Support

Unfortunately, PM2 has no built-in startup support for Windows. PM2’s documentation recommends using either pm2-windows-service or pm2-windows-startup. However, both of these projects have some real drawbacks.

pm2-windows-startup adds an entry to the registry to start pm2 after user login. Because it does not create a service, PM2 will not be running until a user has logged into the user interface, and will halt when they log out. It has not been updated since 2015.

pm2-windows-service uses node-windows to create a service that runs pm2. This is a much better approach, but it hasn’t been maintained since 2018, has outdated dependencies that cause crashes on setup, and currently fails to run properly on Node 14. It also runs the service as the the Local System user instead of Local Service.

This project creates its own Windows Service using the current version of node-windows and a series of PowerShell scripts inspired by this excellent gist by @maxfierke & @mauron85.

When running on Windows, pm2-installer will:

Configure npm to keep its global files in C:\ProgramData\npm, instead of keeping them in the current user’s %APPDATA%
Install pm2 globally, using an offline cache if necessary
Create the C:\ProgramData\pm2 directory and set the PM2_HOME environmental variable at the machine level
Set permissions both the new npm and pm2 folders so that the Local Service user may access them
Leverage node-windows to install a new Windows service
Use PowerShell to configure the service to run as the Local Service user (due to node-windows#89)
Confirm the service is running properly
Install the pm2-logrotate module so that log files don’t fill up the disk

After that, pm2 will be running in the background the Local Service user. It will persist across reboots and continue running regardless of which user is logged in. To add your app, run pm2 start app.js from an admin command line interface. Make sure to run pm2 save to serialize the process list.

Install

Download the latest version here.

Copy the entire pm2-installer directory onto the target machine, then run:

npm run setup

On Windows, the setup script assumes you have already configured npm to use prefix and cache directories in a location accessible to the Local Service user. If not, it will issue a warning and ask if you’re sure you’d like to proceed.
To set up npm automatically, run configure first:

npm run configure
npm run setup

That’s it.

NOTE: Running npm install is not necessary, unless you’re developing pm2-installer itself and want to lint the project.

Offline Install

pm2-installer is also designed to function without an internet connection. It does this by creating a cache on an internet-connected build machine, then installing from that cache when run on the offline deployment machine.

On an internet-connected build machine running the same OS as the deployment target, run the following:

npm run bundle

This will populate the cache in the project’s directory with the resources required to install offline. Transfer the entire pm2-installer directory onto the deployment target, then run:

npm run setup

pm2-installer will check if it can contact the npm registry and install online if possible, or use the offline cache if not.

Windows Install

There are a couple additional challenges when installing on a fresh Windows machine. The npm global directory is not accessible to other users by default, which means the Local Service user will not be able to locate the pm2 executable. Additionally, if the machine’s PowerShell execution policy is Undefined or Restricted, invoking pm2 in PowerShell will fail- even though the setup script unblocks pm2.ps1.

pm2-installer includes two additional scripts to automatically fix the above issues. Invoking npm run configure will create the C:\ProgramData\npm\, and set npm to use prefix and cache locations in that directory. Running npm run configure-policy checks the machine’s PowerShell execution policy and if it is either undefined or Restricted, updates it to RemoteSigned.

Open an elevated terminal (e.g. right click and select “Run as Admin”) and run the following commands first:

npm run configure
npm run configure-policy

Then, run npm run setup to install the pm2 service.

Additional context for Windows installations

The pm2 service runs as the Local Service user. To interact with pm2, you need to use an elevated terminal (e.g. right click and select “Run as Admin”) before running any commands that interface with the service, e.g. pm2 list.
If you update node and npm, make sure to either manually re-configure your npm & node installations or run npm run configure again.
This project does not currently support nvm for windows. It requires a standard node installation.

Removal

To remove the pm2 service, run:

npm run remove

This will remove the service and completely uninstall pm2.

If you used the configure script on Windows to configure npm, you can revert those settings by running:

npm run deconfigure