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 and Task log to a file. To enable this, add the following configuration to your config.json:

{
  "log": {
    "events": {
      "enabled": true,
      "logger": {
        "filename": "../events.log"
        // other logger options
      }
    },
    "tasks": {
      "enabled": true,
      "logger": {
        "filename": "../tasks.log"
        // other logger options
      },
			"result_logger": {
				"filename": "../task_results.log"
        // other logger options
			}
    }
  }
}

Or you can do this using following environment variables:

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

export SEMAPHORE_TASK_LOG_ENABLED=True
export SEMAPHORE_TASK_LOG_PATH=./tasks.log

Activity (events) logging options

The Activity (events) logging options allow you to configure how Semaphore records user actions and system events to a file. These settings control the behavior of event logging, including whether it's enabled, the format of log entries, and specific logger configurations. When enabled, all user actions (like creating templates, managing teams, or running tasks) will be written to the specified log file according to these settings.

Tasks logging options

The Tasks logging options allow you to configure how Semaphore records task execution details to a file. These settings control the logging of task-related events, including task starts, completions, and their execution status. When enabled, all task operations and their outcomes will be written to the specified log file according to these settings, providing a detailed audit trail of task execution history.

Task results logging options

Logger options

Each line in the file follows this format:

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

Task history

Semaphore stores information about task execution in the database. Task history provides a detailed view of all executed tasks, including their status and logs. You can monitor tasks in real time or review 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, thet 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 and tasks log: Tracks all user actions. Optionally, Pro 2.10+ can write these to a file.
• Task history: 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.