A Beginner's Guide To Kubectl Logs
When attempting to create a comprehensive application that needs various containerized aspects, Kubernetes has rapidly become the go-to solution. With fantastic management systems in place and monitoring tools that help you break down the performance of individual pods and nodes within the systems, it’s hard to deny just how effective Kubernetes is.
What Are Kubernetes Logs?
The system logs within Kubernetes act as centralized locations where records of all the processes and actions that are currently going on, and have been going on, are documented within the ecosystem. These are primarily used for checking to see if all the processes within the system are running correctly. Yet, Kubernetes logs can also be used for debugging, with tracing the steps backward from an error normally leading you to an explanation.
Within logs, you’re able to trace errors to a single component or take an advanced look into the different events that are currently running. For example, Kubernetes logs will allow you access to pod state changes, scheduler decisions, HTTP access logs, and anything that you need to ensure the ongoing health of your system.
What Types of Kubernetes Logs are There?
A central problem that many people find when managing their Kubernetes logs is a lack of understanding of how different parts of the logging system function.
Typically, the Kubernetes log is split into 6 areas:
? Container Logs - Generated directly by containerized applications, these are an overview of your apps.
? Node Logs - Node-level logs allow you to collect specific information about the nodes in operation
? Cluster Logs - All the system logs, both those within components and between different components, are stored here.
? Events Logs - All the information about resource movements, changes, or event errors will be found here.
? Audit Logs - A small section that displays descriptions of all the different calls that are made to the Apiserver of Kubernetes, the audits on any master nodes, and the backend of your Kubernetes API server.
? Ingress Logs - If there are HTTP routes that enter a cluster from an external source, they will be documented here.
Due to the complexity of the Kubernetes ecosystem, it’s no wonder that the logging processes are equally diverse.
What are the best practices for Kubernetes Logging?
While logging in Kubernetes is typically treated as a holistic system, there are actually a few elements that you can tinker with along the way, boosting how effective your logging practices are.
We recommend that you:
? Keep your Log Formats Consistent
? Impose Resource Limits
? Understand the Shortcuts
Let’s break these down further.
Keep Your Log Formats Consistent
Much like using labels in Kubernetes, this system is only at its full potential when it is consistently deployed across your whole ecosystem. As multiple different units within your compartmentalized system will generate entries to the log, without proper formatting, things can rapidly get overly confusing.
We recommend that you configure stdout and stderr before you start building extensively with Kubernetes. These will then allow you to add labels and specific metadata requirements to your logs, creating a system that is more easily categorized and stored.
Additionally, a structured log that has free-flowing data in and out of it is much easier to run analysis on. If you want to deploy the Elasticsearch function, then a well-formatted log will have significantly reduced latency thanks to the natural structure.
Impose Resource Limits
In an ecosystem where any given Kubernetes cluster can have up to 5000 individual nodes all working together, with a maximum of 150,000 pods, it’s no wonder that the entire system can become incredibly resource-intensive. Due to this, one of the best practices you can do to reduce the volume of the logs that you are producing is to use DaemonSets.
DaemonSet is a function that allows pods to be directly assigned to nodes when they’re added to the cluster. With this, you’re able to run containers continuously in the background, ensuring that similar structures are deployed at the same time and accounted for when a new pod fits into this system.
With this, you’re able to rely on Daemon sets to optimize the distribution of your system resources. All you need to do is set a resource limit within the configurations of DaemonSet, allowing you to more effectively manage the system as a whole.
Understand the Shortcuts for Kubectl
As the primary method through which you interact with a cluster in Kubernetes, understanding how the Kubectl command line is used is vital. When it comes to managing Kubectl logs, it’s vital that you are familiar with all the most important commands that you’ll have to run on a regular basis.
From switching context and getting the name of a container that a running pod is included in to creating private registry folders or even getting additional contexts, there is a Kubectl command for everything.
To effectively use this system, you need to be able to know the commands automatically, using them to rapidly maneuver through your logs and pull out the information that you’re searching for.
Effectively managing your Kubernetes ecosystem requires a great deal of knowledge about formatting and the best logging processes. From learning all the commands needed to explore the logs to ensure that entries come in formatted correctly, there are a lot of steps you can take to make the process easier for yourself.
After incorporating the tips in this article into your daily processes on Kubernetes, you’ll be well on your way to managing your system with a greater level of efficiency.