Networking Concepts

Networking is the backbone of distributed systems. Whether you’re deploying containers, managing Kubernetes clusters, or building cloud infrastructure, understanding how names resolve, traffic routes, and services discover each other is non-negotiable.

DNS & Name Resolution

PageDescription
DNS FundamentalsWhat DNS is, why it exists, and how it maps names to IPs
DNS Record TypesA, CNAME, MX, NS, TXT, SRV — anatomy and use cases
DNS CachingBrowser, OS, router, ISP, and resolver-level caching
DNS Hierarchy and Root ServersRoot, TLD, and authoritative servers; anycast
DNS Resolution FlowStep-by-step query walkthrough
Local DNS Configuration/etc/hosts, /etc/resolv.conf, and troubleshooting
Public DNS ResolversCloudflare 1.1.1.1, Google 8.8.8.8, and when to switch

Tools

PageDescription
nslookupDNS lookup command-line tool

Kubernetes Networking

PageDescription
CoreDNSKubernetes cluster DNS and service discovery
Kubernetes ServicesClusterIP, NodePort, LoadBalancer, ExternalName
Kubernetes Network PoliciesPod-to-Pod traffic control and zero-trust segmentation

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