Understanding Log Levels | Tutorial

hi and hello today let's talk about log levels what they are and the fundamentals of how to use them understanding log levels at the heart of log management lies the concept of log levels in essence a log level is a classification mechanism used to indicate the significance of a specific log message this is why log levels are sometimes called log severity log levels act as a beacon helping us differentiate critical events from routine informative updates within log data when logs do not adhere to standard logging practices it's difficult to derive meaningful Insight from them to address this it's essential to follow best practices in regard to log levels so what are log levels a logging level is a way of classifying or categorizing your logs to convey the importance of a log message it offers a straightforward yet potent way to distinguish log events when used correctly in your application log level serve as a quick indicator of the events importance and not only for humans but also for your alerting system think of log levels as a filter filter of sort they convey the level of importance that a log is it could be critical system information or purely informative data you don't want an alert for run-of-the-mill information but you do want a big alert when a big event happens log levels assist in reducing information overload and help relieve alert fatigue but first a brief history of log levels where did they come from the concept of log levels originated with CIS log developed in the early 80s syis log introduced severity levels and since then different programming language and logging Frameworks have emerged each with their own logging capabilities while formats and destinations might vary a little bit log levels remain a common feature across all Frameworks common logging levels in most logging Frameworks you'll encounter the following log levels Trace debug info warning error and critical let's take a look at each Trace Trace is the most detailed level reserved for rare cases where you need full visibility into your application and thirdparty libraries it provides extremely granular information Trace is typically used when you want to trace the flow of execution within your code including function entry and exit points variable values and detailed timing information like tracking the steps of a complex algorithm in a performance critical application debug debug is less granular than Trace but more detailed than other log levels it's not generally used on a daily basis as it is more suitable for diagnosing issues troubleshooting and testing applications in a controlled environment debug is useful for tracking variables function calls or specific events during development for instance you might use debug to log database queries HTTP request or detailed information about the internal state of your application during debugging info the info log level indicates that something noteworthy happened in the application such as entering a specific state it provides an informative context but doesn't require regular attention or direct action during normal operations info is ideal for recording important milestones in your application's lifestyle for instance you might log when a user successfully logs in when a background task is completed or when a new version of your application starts the warning log level the warning log level signifies unexpected Behavior while not expected this Behavior doesn't actually disrupt the application but warrants your attention it's used for situations that are out of the ordinary but don't cause the application to fail you should use warning when you encounter recoverable issues or unusual conditions like if an application receives an unusual input that it can handle but isn't typical or when a resource is running low but hasn't caused a failure yet think of it like a gasl light on your vehicle it's a warning and it's informative about the current situation and sure you might be able to squeeze by but it's not wise to continue in that state for very long error the error log level is reserved for when the application encounters an issue that prevents some functionalities but continues to work correctly as a whole it indicates a problem but not a total failure error is an appropriate categorization for capturing issues that need investigation but but don't result in the application crashing take for example a database connection failure or an API request timeout or a file not being found sure the application still might work to a degree but you should definitely look into it and fix it and finally critical the critical log level indicates a crucial failure there is a crucial business functionality that is no longer operational this level indicates a severe issue that makes the application unusable and needs immediate attention the critical log level should be used sparingly for catastrophic failures that render the application unusable or endangers data Integrity think of it like a server crash a security breach or database corruption that leads to data loss keep in mind all errors are bad but not all errors are created equally so don't make each event catastrophic when in reality it's just a warning or an error now let's make sense of it all while log levels look pretty on their own to make sense of log levels in your log events there are two main actions that will need to be performed filtering and alerting filtering by log levels lets you focus on specific severity levels of interest and is crucial for troubleshooting if you cannot filter your logs they're kind of pointless as log levels are a tag of sorts so you can identify and address critical issues and troubleshoot effectively so get a tool that allows you to filter well through your massive amounts of log data but filtering isn't everything you wouldn't know to search or filter for something if you were not first a alerted to an issue implementing alerts based on log levels allow you to receive notifications for critical and fatal events that require immediate action having the ability to utilize log levels as a way of triggering alerts and sending out notifications to the appropriate team is an absolute must alerting should be reserved only for the more serious events and log events and alerts should be actionable and they shouldn't overwhelm you with non-critical notifications if you're interested in the logging and infrastructure monitoring solution that I've been using throughout this video video check out the link below or visit cex.com and check out the free demo there in conclusion choosing the right log level for particular events during application development is a long and tedious But ultimately vital process proper log levels not only help you troubleshoot but really help with concise alerting and effective log management as systems generate increasing volumes of log messages using appropriate log levels becomes crucial for maintaining log quality remember the quality of your logs directly impacts effectiveness of log Management Solutions solons use log levels wisely to ensure that your logs remain useful and contribute to efficient log management and as always May the logs be with you

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Keywords: logging, logger, java, logging java, node js logging, how to logging, devops logging, centralized logging, logging solution, log monitoring, fluentd, fluentd logging, log levels, log levels java, how to log java, best logging, logging tools, tools for logging application, jvm logging, java logging, node.js logging

Id: 7EzTZEmPcIQ

Length: 6min 39sec (399 seconds)

Published: Wed Nov 22 2023