Logs

Semaphore writes server logs to stdout and stores Task and Activity logs in a database, centralizing key log information and eliminating the need to back up log files separately. The only data stored on the file system is caching data.

Server log

Semaphore does not log to files. Instead, all application logs are written to stdout.
If Semaphore is running as a systemd service, you can view the logs with the following command:

journalctl -u semaphore.service -f

This provides a live (streaming) view of the logs.

Activity log

The Activity Log captures all user actions performed in Semaphore, including:

• Adding or removing resources (e.g., Templates, Inventories, Repositories).
• Adding or removing team members.
• Starting or stopping tasks.

Pro version 2.10 and later

Semaphore Pro 2.10+ supports writing the Activity Log to a file. To enable this, add the following configuration to your config.json:

{
  "log": {
    "events": {
      "enabled": true,
      "path": "../events.log"
    }
  }
}

Or you can do this using following environment variables:

export SEMAPHORE_EVENT_LOG_ENABLED=True
export SEMAPHORE_EVENT_LOG_PATH=./events.log

Each line in the file follows this format:

2024-01-03 12:00:34 user=234234 object=template action=delete

Task log

Task Logs detail the execution of tasks in Semaphore. You can view them in real-time or access historical logs through the web interface.

Configuring task retention

By default, Semaphore stores all tasks in the database. If you run a large number of tasks, the can occupy a significant amount of disk space.

You can configure how many tasks are retained per template using one of the following approaches:

1. Environment Variable

   SEMAPHORE_MAX_TASKS_PER_TEMPLATE=30
   

2. config.json Option

   {
     "max_tasks_per_template": 30
   }
   

When the number of tasks exceeds this limit, the oldest Task Logs are automatically deleted.

Summary

• Server log: Written to stdout; viewable via journalctl if running under systemd.
• Activity log: Tracks all user actions. Optionally, Pro 2.10+ can write these to a file.
• Task log: Stores real-time and historical task execution logs. Retention is configurable per template.

Following these guidelines ensures you have proper visibility into Semaphore UI operations while controlling storage usage and log retention.