Ecosystem File

Configuration File

When managing multiple applications with PM2, use a JS configuration file to organize them.

Generate configuration

To generate a sample configuration file you can type this command:

$ pm2 init simple

This will generate a sample ecosystem.config.js:

module.exports = {
  apps : [{
    name   : "app1",
    script : "./app.js"
  }]
}

If you are creating your own configuration file, make sure it ends with .config.js so PM2 is able to recognize it as a configuration file.

Acting on Configuration File

Seamlessly than acting on an app you can start/stop/restart/delete all apps contained in a configuration file:

# Start all applications
pm2 start ecosystem.config.js

# Stop all
pm2 stop ecosystem.config.js

# Restart all
pm2 restart ecosystem.config.js

# Reload all
pm2 reload ecosystem.config.js

# Delete all
pm2 delete ecosystem.config.js

Act on a specific process

You can also act on a particular application by using its name and the option --only <app_name>:

pm2 start   ecosystem.config.js --only api-app

Note: the --only option works for start/restart/stop/delete as well

You can even specify multiple apps to be acted on by specifying each app name separated by a comma:

pm2 start ecosystem.config.js --only "api-app,worker-app"

Switching environments

You can specify different environment variable set via the env_* option.

Example:

module.exports = {
  apps : [{
    name   : "app1",
    script : "./app.js",
    env_production: {
       NODE_ENV: "production"
    },
    env_development: {
       NODE_ENV: "development"
    }
  }]
}

Now to switch between variables in different environment, specify the --env [env name] option:

pm2 start process.json --env production
pm2 restart process.json --env development

Attributes available

Application behavior and configuration can be fine-tuned with the following attributes:

General

Advanced features

Log files

Control flow

Deployment

Considerations

All command line options passed when using the JSON app declaration will be dropped i.e.

CWD

cwd: your JSON declaration does not need to reside with your script. If you wish to maintain the JSON(s) in a location other than your script (say, /etc/pm2/conf.d/node-app.json) you will need to use the cwd feature (Note, this can be really helpful for capistrano style directory structures that uses symlinks). Files can be either relative to the cwd directory, or absolute (see example below).

CLI/JSON options

All the keys can be used in a JSON configured file, but will remain almost the same on the command line e.g.:

exec_mode         -> --execute-command
max_restarts      -> --max-restarts
force             -> --force

Using quotes to make an ESC, e.g.:

$pm2 start test.js --node-args "port=3001 sitename='first pm2 app'"

The nodeArgs argument will be parsed as

[
  "port=3001",
  "sitename=first pm2 app"
]

but not

[
  "port=3001",
  "sitename='first",
  "pm2",
  "app'"
]

Disabling logs

You can pass /dev/null to error_file or out_file to disable logs saving. Note: starting PM2 2.4.0, /dev/null or NULL disable logs independently of the platform.

Logs suffix

You can disable automatic ID suffixes on logs (e.g. app-name-ID.log) by passing enabling the option merge_logs: true

Environment definition

You’ll need to use --env <envname> to tell pm2 to use specific environment defined inside a process file :

{
  "apps" : [{
    "name"        : "worker-app",
    "script"      : "./worker.js",
    "watch"       : true,
    "env": {
      "NODE_ENV": "development"
    },
    "env_production" : {
       "NODE_ENV": "production"
    }
  },{
    "name"       : "api-app",
    "script"     : "./api.js",
    "instances"  : 4,
    "exec_mode"  : "cluster"
  }]
}

In this example, you will run pm2 start ecosystem.json and it will start your application with the default environment (in development so). Then you use pm2 start ecosystem.json --env production and it will use the attribute env_<name> where name is production here, so it will start your app with NODE_ENV=production.

Special ext_type

• min_uptime Value of min_uptime can be:
  • Number e.g. "min_uptime": 3000 means 3000 milliseconds.
  • String Therefore, we are making it short and easy to configure: h, m and s, e.g.: "min_uptime": "1h" means one hour, "min_uptime": "5m" means five minutes and "min_uptime": "10s" means ten seconds (those will be transformed into milliseconds).
• max_memory_restart Value of max_memory_restart can be:
  • Number e.g. "max_memory_restart": 1024 means 1024 bytes (NOT BITS).
  • String Therefore, we are making it short and easy to configure: G, M and K, e.g.: "max_memory_restart": "1G" means one gigabyte, "max_memory_restart": "5M" means five megabytes and "max_memory_restart": "10K" means ten kilobytes (those will be transformed into byte(s)).

• Optional values For example exec_mode can take cluster (cluster_mode) or fork (fork_mode) as possible values.

• Things to know
  • "instances": 0 means that PM2 will launch the maximum processes possible according to the numbers of CPUs (cluster mode)
  • array args, node_args and ignore_watch could be type of Array (e.g.: "args": ["--toto=heya coco", "-d", "1"]) or string (e.g.: "args": "--to='heya coco' -d 1")