log

Manage logging and debug output

The mullvad log command controls logging behavior and output verbosity for the Mullvad VPN daemon.

Usage

mullvad log <SUBCOMMAND>

Subcommands

get

Display current log settings.

mullvad log get

Example output:

Log level: debug
Log to file: true
Log to console: false

set-level

Set the logging level.

mullvad log set-level <LEVEL>

Available levels:

• error - Only errors
• warn - Warnings and errors
• info - Informational messages, warnings, and errors (default)
• debug - Debug information plus all above
• trace - Very verbose tracing plus all above

set-file

Enable or disable logging to file.

mullvad log set-file <on|off>

Examples

Check current settings

mullvad log get

Enable debug logging

mullvad log set-level debug

Useful for troubleshooting connection issues.

Enable trace logging

mullvad log set-level trace

Trace logging is very verbose and can impact performance. Only use when debugging specific issues.

Reset to default

mullvad log set-level info

Disable file logging

mullvad log set-file off

Reduces disk I/O but makes troubleshooting harder.

Log file locations

When file logging is enabled:

Linux:

• /var/log/mullvad-vpn/daemon.log
• Systemd journal: journalctl -u mullvad-daemon

macOS:

• /var/log/mullvad-vpn/daemon.log

Windows:

• C:\ProgramData\Mullvad VPN\daemon.log

Log rotation

Logs are automatically rotated:

• Maximum size: 10 MB per file
• Keeps 3 rotated files
• Old files are compressed or deleted

When to use different log levels

error

Use when:

• Disk space is critically low
• You only need to see failures
• Performance is paramount

warn (default)

Use for:

• Normal operation
• Production systems
• When you don’t need detailed diagnostics

info

Use when:

• You want to see connection events
• Monitoring configuration changes
• General operational visibility

debug

Use when:

• Troubleshooting connection issues
• Debugging relay selection
• Investigating firewall rules
• Working with Mullvad support

trace

Use when:

• Debugging specific protocol issues
• Analyzing packet flow
• Detailed performance analysis
• Requested by Mullvad developers

Debugging workflow

# 1. Enable debug logging
mullvad log set-level debug

# 2. Reproduce the issue
mullvad connect
# ... wait for issue to occur

# 3. Collect logs
sudo journalctl -u mullvad-daemon --since "10 minutes ago" > issue-logs.txt
# or on non-systemd systems:
sudo cat /var/log/mullvad-vpn/daemon.log > issue-logs.txt

# 4. Reset log level
mullvad log set-level info

# 5. Submit logs to support

Privacy considerations

Logs may contain:

• Relay server IP addresses
• Connection timestamps
• Network interface names
• System configuration details

Logs do NOT contain:

• Your account number
• DNS queries
• Websites visited
• Tunnel traffic content

Mullvad’s privacy policy applies to logs. If sharing logs with support, review them first to ensure you’re comfortable with the information disclosed.

Environment variable override

For daemon-level logging configuration, use environment variables:

# Set log level via environment (Linux)
sudo systemctl edit mullvad-daemon.service

Add:

[Service]
Environment="RUST_LOG=debug"

See Environment Variables for more options.

Performance impact

Level	CPU Impact	Disk I/O	Disk Space
error	Minimal	Minimal	Very low
warn	Minimal	Low	Low
info	Low	Low	Moderate
debug	Moderate	Moderate	High
trace	High	High	Very high

Exit status

• 0 - Success
• 1 - Invalid log level or daemon error

Related commands

• factory-reset - Clears all logs
• status - Check connection status

Related documentation

• Environment Variables - Daemon-level logging config
• File Paths - Log file locations
• Troubleshooting - Using logs to debug issues