diff --git a/content/day-1/04_dns-debugging.md b/content/day-1/04_dns-debugging.md new file mode 100644 index 0000000..71e6e52 --- /dev/null +++ b/content/day-1/04_dns-debugging.md @@ -0,0 +1,53 @@ +--- +title: Understanding and Debugging DNS in Kubernetes Clusters +weight: 4 +tags: + - +--- + + +{{% button href="https://github.com/mqasimsarfraz/talks/tree/main/CloudNativeRejekts-2025" style="transparent" icon="person-chalkboard" %}}Slides{{% /button %}} + + + +## Baseline + +### DNS Components + +```mermaid +graph LR + Application-->NodeLocalDNS-->CoreDNS-->Upstream +``` + +### Problems + +- Many hidden systems +- Not easy to trace across clusters + +## Tools + +> Demo queries are located in the slides and were executed during the stream + +### CoreDNS Log Plugin + +- Core-Plugin (just needs to be activated) +- Logs all requests to stdout + +### Hubble + +- Cilium observability needs cilium l7 proxy, runs as deamonset +- Needs CiliumNetworkPolicies for AppPod and CoreDNS +- Metrics, UI and cli with jq (and protocol filter) + +### Inspector Gadget + +- Toolset for Kubernetes and Linux that can be customized +- Runns as daemonset or debug pod - gadgets are distributed as containers (via artifactorhub) +- DNS-Gadget: Trace via ebpf, post process with wasm + + +## Overview + +- CoreDNS: Great for initial, nut only CoreDNS +- Hubble: Compact overview, but cilium needed with special configs +- Inspector Gadget: Rich DNS traces, limited tcp support \ No newline at end of file diff --git a/content/day-1/_index.md b/content/day-1/_index.md index 6670b83..4c5a9db 100644 --- a/content/day-1/_index.md +++ b/content/day-1/_index.md @@ -10,4 +10,10 @@ The second and last day of cloud native rejekts and (some might say most importa - My Talk: [Evaluating Global Load Balancing Options for Kubernetes in Practice](todo:) - Service Mesh Intro + Comparison: [The service mesh wars - a new hope for kubernetes](../03_service-mesh) -- iNTRO TO OPERATORS: [The Hidden Brains of Kubernetes: Meet Controllers Powering the Cloud](../02_controllers) \ No newline at end of file +- Intro to operators: [The Hidden Brains of Kubernetes: Meet Controllers Powering the Cloud](../02_controllers) + +## Other stuff I learned or people i talk to + +- Take a deeper look into CoreDNS plugins +- A bunch of nice people that heard my talk and had questions +- Someone from Ampere that would like to help me to convince the infra team to get arm nodes \ No newline at end of file