Want to learn more about Linux logging? Check out this list of the six most common Linux logging issues.
Linux users can access Linux logs, which serve as a timeline that maps events that have taken place in the operating system. These logs are incredibly valuable and can be used to troubleshoot problems and flag issues as and when they occur. If you’re looking to learn about Linux logging best practices, you should start by learning about the most common Linux logging issues. Start reading articles like this one and the other articles linked here. This is a good starting point. Let’s find out more.
Checking the Wrong Logs
Linux logs can be grouped into four primary categories: application logs, event logs, service logs, and system logs. There are huge numbers of logs contained within each of these categories, so to utilize logs effectively it’s essential that you know what you’re looking for.
Take the time to study your log systems and learn where specific information is located. There are several important log files you should be checking and monitoring – so you should know more about those log files. For example,
/var/log/auth.log stores authentication events and user authorization information,
/var/log/messages is used to store non-critical messages and system activity data, and
/var/log/boot.log stores system boot messages.
By understanding what data particular logs store you’ll be able to more efficiently get to the bottom of problems that arise within your system.
Ignoring Log Levels
Linux logs differ in importance. Each log should be on a particular level, and this level should indicate how essential the data stored within that log is. What this means is that if there is an issue within a log, you’ll know immediately just how urgent the situation is and be able to plan your next move accordingly.
At one end of the scale is the Trace level, which contains logs that detail application performance information. At the other end is the Critical level, which contains information on fatal system errors that completely disrupt or destroy processes.
Levels are absolutely critical when using logs, you should never ignore them and always ensure your logs are segmented and easily identifiable.
Creating Too Many Logs
It can be easy to create logs for absolutely everything you can think of. After all, the more information at your disposal the better, right? This isn’t necessarily the case. In fact, creating too many logs can quickly become overwhelming. You’ll have far too much data to realistically manage, and crucial information could end up getting lost. Disabling logs for various services and apps on Linux is pretty straightforward.
However, it’s important that you avoid going too far in the other direction. If you don’t have enough logs, you could find that critical information is unavailable. If issues arise in your system, not having an adequate number of logs could make it impossible to address and rectify the situation.
This is a delicate balancing act that can be tricky to get right, but doing so is essential if you want to maximize the potential benefits Linux logging can offer you.
Including Sensitive Information in Logs
While logs can prove invaluable for cybersecurity purposes, they can also pose a threat if they are not managed and handled in the correct way. You should never store personal or sensitive information in logs, as these can be vulnerable should you suffer a cyberattack or a data breach. Things like passwords, contact data, and banking information should never be stored in logs.
As well as causing potential security issues, storing personal or sensitive data in logs can be a direct breach of data privacy laws and regulations. This means you could end up facing severe legal repercussions if you are using logs to store personal information.
When writing logs, it’s important to follow a set format to ensure your logs are consistent across your entire system. Don’t use manual print, as this can easily lead to mistakes and errors.
Logs must be accessible and easy to understand, regardless of who is checking them. By following a standard recognized format, such as JSON, you can ensure your logs remain uniform and consistent.
Always remember to include the date and time as part of your log format. This can make it easier to sift through data and find information that is relevant to the situation at hand.
Not Rotating Logs
Log files can grow quicker than you might expect. As they track and record messages, they can rapidly balloon in size, and you may find they become bloated and unmanageable. What’s more, oversized log files can even cause storage and memory issues in your system.
Log rotation is the process of deleting older files in a system. You can set a threshold so that, when a log reaches a certain size, rotation will take place to trim it down and reduce its footprint. This is a key strategy in log management and should never be overlooked.
Conclusion on Linux Logging Issues
Linux logs are incredibly valuable. They can be used for everything from assessing application performance to checking for signs of cybersecurity threats like brute force attacks. However, it’s essential you follow the best Linux logging best practices if you want to make the most out of this strategy. Use this guide to learn about common Linux logging issues and ensure you avoid repeating these mistakes.