Debug Levels
Learning Focus
By the end of this lesson you will know how to set error log debug levels and when to increase or decrease verbosity.
Available Levels
| Level | When to Use | Volume |
|---|---|---|
| ERROR | Production default | Low |
| WARNING | Investigating intermittent issues | Moderate |
| NOTICE | Routine operational monitoring | Moderate |
| INFO | Detailed operation tracking | High |
| DEBUG | Active troubleshooting only | Very high |
Changing the Level
In WebAdmin
- Server Configuration → Log → Error Log
- Set Log Level to the desired verbosity
- Save and Graceful Restart
Practical Usage
# Set to DEBUG, reproduce the issue, then check logs
tail -100 /usr/local/lsws/logs/error.log
# After troubleshooting, set back to ERROR
# High debug levels on busy servers generate massive output
warning
Never leave DEBUG level enabled on production servers. It causes significant disk I/O and can fill the disk rapidly.
Key Takeaways
- Use ERROR for production and DEBUG temporarily for troubleshooting.
- Always revert to low verbosity after diagnosing an issue.
- High debug levels cause significant disk I/O on busy servers.
What's Next
- Continue to Error Log Troubleshooting for reading and interpreting error logs.