Can we start n8n main and workers in same machine

[Jekylls]

@shakthipsg

DB_TYPE postgresdb
N8N_BLOCK_ENV_ACCESS_IN_NODE false
Path C:\Users\Administrator\AppData\Local\Microsoft\WindowsApps;C:\Users\Administrator\AppData\Roaming\npm
EXECUTIONS_MODE queue
OFFLOAD_MANUAL_EXECUTIONS_T… true
N8N_ENDPOINT http://localhost:5678
N8N_MIGRATE_FS_STORAGE_PATH true
DB_POSTGRESDB_USER n8n_user
QUEUE_BULL_REDIS_HOST localhost
N8N_LOG_LEVEL info
DB_POSTGRESDB_DATABASE n8n_db
N8N_ENCRYPTION_KEY *****
N8N_LOG_OUTPUT console
NODES_EXCLUDE
QUEUE_BULL_REDIS_PORT 6379
DB_POSTGRESDB_HOST localhost
DB_POSTGRESDB_PASSWORD n8n
DB_POSTGRESDB_PORT 5432
DB_POSTGRESDB_SCHEMA n8n

PM2 start configuration for Main and Worker instances:
module.exports = {
apps: [
{
name: “n8n-main”,
script: “C:\Users\Administrator\AppData\Roaming\npm\node_modules\n8n\bin\n8n”,
args: “”,
interpreter: “node”,
instances: 1, // Always keep main as 1
exec_mode: “fork”, // Important for n8n workers
env: {
N8N_RUNNERS_MODE: “internal”,
N8N_RUNNERS_ENABLED: “true”,
N8N_RUNNERS_BROKER_PORT: “5679”
}
},
{
name: “n8n-worker-01”,
script: “C:\Users\Administrator\AppData\Roaming\npm\node_modules\n8n\bin\n8n”,
args: “worker --concurrency 50”,
interpreter: “node”,
instances: 1, // Scale workers here
exec_mode: “fork”, // Important for n8n workers
env: {
N8N_RUNNERS_MODE: “internal”,
N8N_RUNNERS_ENABLED: “true”,
N8N_RUNNERS_BROKER_PORT: “5680”,
N8N_RUNNERS_TASK_BROKER_URI: “127.0.0.1:5680”
}
},
{
name: “n8n-worker-02”,
script: “C:\Users\Administrator\AppData\Roaming\npm\node_modules\n8n\bin\n8n”,
args: “worker --concurrency 50”,
interpreter: “node”,
instances: 1, // Scale workers here
exec_mode: “fork”, // Important for n8n workers
env: {
N8N_RUNNERS_MODE: “internal”,
N8N_RUNNERS_ENABLED: “true”,
N8N_RUNNERS_BROKER_PORT: “5681”,
N8N_RUNNERS_TASK_BROKER_URI: “127.0.0.1:5681”
}
},
{
name: “n8n-worker-03”,
script: “C:\Users\Administrator\AppData\Roaming\npm\node_modules\n8n\bin\n8n”,
args: “worker --concurrency 50”,
interpreter: “node”,
instances: 1, // Scale workers here
exec_mode: “fork” , // Important for n8n workers
env: {
N8N_RUNNERS_MODE: “internal”,
N8N_RUNNERS_ENABLED: “true”,
N8N_RUNNERS_BROKER_PORT: “5682”,
N8N_RUNNERS_TASK_BROKER_URI: “127.0.0.1:5682”
}
},
{
name: “n8n-worker-04”,
script: “C:\Users\Administrator\AppData\Roaming\npm\node_modules\n8n\bin\n8n”,
args: “worker --concurrency 50”,
interpreter: “node”,
instances: 1, // Scale workers here
exec_mode: “fork”, // Important for n8n workers
env: {
N8N_RUNNERS_MODE: “internal”,
N8N_RUNNERS_ENABLED: “true”,
N8N_RUNNERS_BROKER_PORT: “5683”,
N8N_RUNNERS_TASK_BROKER_URI: “127.0.0.1:5683”
}
},
{
name: “n8n-worker-05”,
script: “C:\Users\Administrator\AppData\Roaming\npm\node_modules\n8n\bin\n8n”,
args: “worker --concurrency 50”,
interpreter: “node”,
instances: 1, // Scale workers here
exec_mode: “fork”, // Important for n8n workers
env: {
N8N_RUNNERS_MODE: “internal”,
N8N_RUNNERS_ENABLED: “true”,
N8N_RUNNERS_BROKER_PORT: “5684”,
N8N_RUNNERS_TASK_BROKER_URI: “127.0.0.1:5684”
}
}
]
};

@shakthipsg Try this change and let me know your outcome I will explain after if working.

const path = require('path');

// Common environment variables for all instances
const sharedEnv = {
  // Database Config
  DB_TYPE: "postgresdb",
  DB_POSTGRESDB_HOST: "localhost",
  DB_POSTGRESDB_PORT: "5432",
  DB_POSTGRESDB_DATABASE: "n8n_db",
  DB_POSTGRESDB_USER: "n8n_user",
  DB_POSTGRESDB_PASSWORD: "n8n",
  DB_POSTGRESDB_SCHEMA: "n8n",
  N8N_ENCRYPTION_KEY: "*****", // Replace with your actual key

  // Redis / Queue Config
  EXECUTIONS_MODE: "queue",
  QUEUE_BULL_REDIS_HOST: "localhost",
  QUEUE_BULL_REDIS_PORT: "6379",

  // General Config
  N8N_LOG_LEVEL: "info",
  N8N_LOG_OUTPUT: "console",
  N8N_BLOCK_ENV_ACCESS_IN_NODE: "false",
  N8N_MIGRATE_FS_STORAGE_PATH: "true",
  N8N_ENDPOINT: "http://localhost:5678",
  OFFLOAD_MANUAL_EXECUTIONS_TO_WORKERS: "true",

  // Runner/Broker Config (CRITICAL)
  N8N_RUNNERS_ENABLED: "true",
  N8N_RUNNERS_MODE: "internal",
  N8N_RUNNERS_BROKER_PORT: "5679" // This is the ONLY port the broker uses
};

// Windows path to n8n binary (Note the double backslashes)
const n8nPath = "C:\\Users\\Administrator\\AppData\\Roaming\\npm\\node_modules\\n8n\\bin\\n8n";

module.exports = {
  apps: [
    {
      name: "n8n-main",
      script: n8nPath,
      args: "start",
      interpreter: "node",
      env: {
        ...sharedEnv
      }
    },
    // Generate 5 Workers
    ...[1, 2, 3, 4, 5].map((i) => ({
      name: `n8n-worker-0${i}`,
      script: n8nPath,
      args: "worker --concurrency 50",
      interpreter: "node",
      env: {
        ...sharedEnv,
        // All workers connect to the SINGLE broker port hosted by Main
        N8N_RUNNERS_TASK_BROKER_URI: "127.0.0.1:5679" 
      }
    }))
  ]
};

** Remember - you must perform pm2 delete n8n before loading this new configuration in order to prevent ghosts from generating.

In JavaScript strings, a single backslash (\) is an escape character. If you use C:\Users, the \U will break the script. I have used double backslashes (\\) in the config above to ensure Windows understands the path.

if there is still error please share output of n8n-error.log

[shakthipsg]

Same issue.

[Jekylls]

@shakthipsg shakthipsg please share errors this is different problem. Share n8n-error.log

[shakthipsg]

Reloaded the instances ‘pm2 reload all’
No update in error logs, only the out logs go updated.

[shakthipsg]

Not able to upload the log files. Here is the latest trace from logs.

worker-1:
n8n Task Broker ready on 127.0.0.1, port 5679
Failed to start Python task runner in internal mode. because Python 3 is missing from this system. Launching a Python runner in internal mode is intended only for debugging and is not recommended for production. Users are encouraged to deploy in external mode. See: Task runners | n8n Docs

There is a deprecation related to your environment variables. Please take the recommended actions to update your configuration:

• N8N_RUNNERS_ENABLED → Remove this environment variable; it is no longer needed.

[license SDK] Skipping renewal on init: renewOnInit is disabled in config
[license SDK] Skipping renewal on init: autoRenewEnabled is disabled in config
[license SDK] Skipping renewal on init: license cert is not due for renewal

All other workers:
Out file has only the below trace.

”””
n8n Task Broker’s port 5679 is already in use. Do you have another instance of n8n running already?
”””

[shakthipsg]

Delete all the process, logs files, and started fresh. Only 1 worker came online. No traces in error logs. Out logs has only the below trace for failed workers.

”””
n8n Task Broker’s port 5679 is already in use. Do you have another instance of n8n running already?
”””