Log File Rotation#

PPM provides built-in log file rotation to help manage disk usage and retain recent logs.

By default, this feature is disabled. When disabled, services inherit stdout and stderr from the PPM daemon, meaning logs are displayed directly in your container console.

Enabling the Logger#

To enable log file management, add the following section to your configuration file:

logger:

Once enabled, PPM will write logs to files instead of forwarding them to the console.

Configuration Options#

You can fine-tune the logger behavior using the following options (shown here with their default values):

logger:
  # Directory where log files are stored
  path: /var/log

  # Maximum number of log files to retain
  # (including the currently active log file)
  max_files: 3

  # Maximum file size before rotation occurs
  max_file_size: 20MiB

Option Details#

• path
  Directory where log files will be written.
  If the directory does not exist, it will be created automatically.
  PPM must have write permissions for this directory.

• max_files
  The maximum number of log files kept per service.
  When the limit is reached, the oldest log file is removed.

• max_file_size
  The size threshold that triggers log rotation.
  When the active log file reaches this size, a new log file is created.

Note: A log file may slightly exceed max_file_size to ensure the last buffered log line is fully written and not truncated.

Log File Naming#

Log files are named using the following format: <service_name>-<date>.log

Each service maintains its own set of rotated log files.

Viewing Logs#

The PPM client provides convenient commands for accessing service logs:

# Dump all logs for a service
ppm log my_service

# Dump the last 200 lines
ppm log my_service -n 200

# Dump last 200 lines and follow output
# (properly handles log rotation)
ppm log my_service -n 200 -f

Example#

Here's an example on how to use the logger, using a service that writes current date every second: