Troubleshooting on Support Tools

Kubernetes DaemonSet Scheduling Troubleshooting: Production Debugging and Node Management Guide

Mon, 24 Aug 2026 00:00:00 -0500

Kubernetes DaemonSet scheduling issues represent some of the most challenging troubleshooting scenarios in production environments, where critical system components fail to deploy across cluster nodes as expected. These issues can cascade into broader infrastructure problems, affecting monitoring, logging, storage, and networking capabilities that underpin entire application ecosystems.

Understanding how to systematically diagnose and resolve DaemonSet scheduling problems requires deep knowledge of Kubernetes scheduling mechanics, node conditions, taints and tolerations, and cluster networking. This comprehensive guide explores advanced troubleshooting methodologies based on real-world production scenarios and provides actionable solutions for complex scheduling challenges.

Prometheus TSDB Compaction Failed: The 64 GiB Index Ceiling and What It Says About Your Cardinality

Tue, 21 Jul 2026 09:00:00 -0500

Prometheus compaction had been running fine for months. Then this showed up in the logs, and kept showing up every couple of hours:

text
level=ERROR source=db.go:1219 msg="compaction failed" component=tsdb err="compact [/var/lib/prometheus/metrics2/01KJQ22FD0C2VFGQC2T8QP70P2 /var/lib/prometheus/metrics2/01KK8B5EK0CPXWDGPRD3H89ZQP /var/lib/prometheus/metrics2/01KKSP6NZ0EYNDGJFJTD3D6N6F]: populate block: add series: write series data: \"/var/lib/prometheus/metrics2/01KKSSF1T0T0T3AN0PJ00WVQGJ.tmp-for-creation/index\" exceeding max size of 64GiB

add padding: \"/var/lib/prometheus/metrics2/01KKSSF1T0T0T3AN0PJ00WVQGJ.tmp-for-creation/index\" exceeding max size of 64GiB"

Searching that string gets you almost nothing: a handful of GitHub issues, no runbook, no explanation. So here is the explanation. Short version: this is a hard limit in the TSDB index file format, not a resource problem. You cannot tune it, add RAM to it, or upgrade past it. It is real and it needs work, but it is not a data-loss event, and the most likely root cause is cardinality. Specifically, the number of distinct series that existed anywhere inside the merged block’s time range, which is a very different number from your current head cardinality.

Distributed System Debugging Tools: Enterprise Kubernetes Troubleshooting Guide

Sat, 13 Jun 2026 00:00:00 -0500

Master distributed system debugging in Kubernetes with comprehensive tools and techniques for tracing, log analysis, performance profiling, and troubleshooting complex microservices architectures in enterprise production environments.

Fixing Helm Upgrades After Kubernetes v1.25: The PDB API Version Trap

Thu, 16 Apr 2026 09:00:00 -0500

During a recent production cluster upgrade from v1.23 to v1.25, we hit a brick wall with Helm that temporarily halted our maintenance window. All our chart updates were properly tested, our backups were verified, and our rollback plan was ready—but Helm stubbornly refused to upgrade critical workloads with a cryptic error about PodDisruptionBudgets. Here’s what happened, how we solved it, and the important lessons that will save you considerable headaches in your future upgrades.

Advanced Docker Container Debugging: A Comprehensive Guide for Troubleshooting Production Issues

Thu, 15 Jan 2026 09:00:00 -0500

Master the art of Docker container debugging with this comprehensive guide. Learn advanced techniques for troubleshooting container issues in production environments, from analyzing logs and interactive debugging to resolving networking problems, optimizing resource usage, and implementing automated debugging workflows.

Linux Directory Permissions Troubleshooting Guide 2025: Complete Path Analysis & Security Auditing

Wed, 10 Dec 2025 10:00:00 -0500

Understanding and troubleshooting directory permissions is crucial for Linux system administration, security, and application deployment. This comprehensive guide covers advanced permission analysis tools, security auditing techniques, common permission issues, and enterprise-grade access control management strategies.

Dell iDRAC Session Management & Troubleshooting Guide 2025: Complete Connection Control & Monitoring

Mon, 08 Sep 2025 10:00:00 -0500

Dell iDRAC session management is critical for maintaining reliable remote access to PowerEdge servers. This comprehensive guide covers session troubleshooting, automated monitoring, connection pooling, enterprise-scale management strategies, and prevention techniques for session exhaustion issues.

Comprehensive Guide to Locating and Analyzing Ollama Server Logs Across Platforms

Thu, 17 Apr 2025 00:00:00 -0500

When running Ollama for local AI model management, understanding how to access server logs is essential for effective troubleshooting and optimization. This comprehensive guide walks you through accessing Ollama logs across various operating systems and deployment environments.

Is Your Pod’s Environment Variable Not Resolving a Reference to Another Variable?

Fri, 18 Oct 2024 19:26:00 -0500

Environment variables play a crucial role in configuring Kubernetes Pods, but things can quickly go wrong when these variables fail to reference other variables correctly. This can lead to application misconfigurations or runtime errors within the container.

In this post, we’ll explore why a Kubernetes Pod’s environment variable might not resolve references to another variable, common causes of the issue, and how to troubleshoot and fix it.

Viewing Logs from the Previous Container Instance When Your Container Is Crashing

Fri, 18 Oct 2024 19:26:00 -0500

When a Kubernetes Pod enters a CrashLoopBackOff state, it can be challenging to figure out what’s going wrong, especially since the container may be repeatedly crashing and restarting. In these cases, viewing the logs from the previous instance of the container can provide critical insight into why the container is failing.

In this post, we’ll walk through how to view the logs from a previous container instance using the kubectl logs command and provide troubleshooting tips for common issues.

Kubernetes CrashLoopBackOff Example

Thu, 17 Oct 2024 19:26:00 -0500

In Kubernetes, one of the most common issues users encounter is the CrashLoopBackOff status for a Pod. This error indicates that a container in the Pod is crashing repeatedly, causing Kubernetes to restart it in a loop with increasing wait times between restarts. Understanding how to troubleshoot and resolve this issue is crucial for maintaining a healthy cluster.

In this post, we’ll explore what CrashLoopBackOff means, provide a real-world example, and show you how to fix it.

How To Fix OOMKilled in Kubernetes

Sat, 21 Sep 2024 19:26:00 -0500

One of the most common issues Kubernetes users encounter is the OOMKilled error, which occurs when a pod gets terminated because it ran out of memory. This error can disrupt application performance and cause instability in your environment. In this post, we’ll cover the reasons behind OOMKilled errors and the steps you can take to fix them.

Configuring Kube-apiserver Audit Logs in RKE2

Wed, 11 Sep 2024 03:26:00 -0500

Audit logs in Kubernetes are vital in monitoring and securing your cluster. They help you track API requests, identify configuration changes, and trace actions to their source. In RKE2 (Rancher Kubernetes Engine 2), you can configure kube-apiserver audit logs to capture high-level and detailed information about what happens in your cluster.

In this post, we’ll walk through how to set up basic and detailed audit logging for the kube-apiserver in RKE2, providing examples to help you monitor API activities effectively.

Using Audit Logs to Track Changes in Fleet or ArgoCD

Wed, 11 Sep 2024 02:26:00 -0500

In environments where GitOps tools like Fleet or ArgoCD are used to manage Kubernetes clusters, changes can be rapid and automated. However, when things go wrong—such as deployments failing, or configurations being overwritten—it’s important to know who made the change, what was changed, and when the change occurred.

In this post, we’ll focus on how you can use audit logs from Rancher, Fleet, and ArgoCD to track down the root cause of issues. We’ll walk through practical examples, and show you how to trace changes back to the IP address or user responsible.