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Alertmanager Routing and Silences
Alertmanager takes firing alerts from Prometheus and decides who gets paged, grouped how, and when. Here's the routing tree, grouping, inhibition, and silences.
October 24, 2026GTP and the Mobile Packet Core
GTP is the tunnelling protocol that carries subscriber data through the mobile core. Here's GTP-C (signalling) vs GTP-U (user plane), TEIDs, bearers, and GTP security.
October 24, 2026A node_exporter Metrics Guide
node_exporter emits hundreds of host metrics. Here are the two dozen that matter, the PromQL to graph them, and sensible alert thresholds.
October 24, 2026Loki for Logs
Loki is 'Prometheus for logs' — it indexes labels, not full text, so it's cheap. Here's LogQL, the cardinality rule, and how it differs from Elasticsearch.
October 24, 2026Feature Flags in Practice
Feature flags decouple deploy from release. Here's the four flag types, targeting and percentage rollout, kill switches, and how to stop flags from becoming permanent tech debt.
October 24, 2026Artifact Repositories: Nexus and Artifactory
A private artifact repository proxies public registries (npm, PyPI, Maven, Docker), hosts your own builds, and gives you retention control and a single auth point. Here's the model.
October 24, 2026eSIM and Remote SIM Provisioning
An eSIM is a reprogrammable chip (eUICC) that holds downloadable operator profiles. Here's the GSMA RSP architecture — SM-DP+, SM-DS, LPA — and the profile lifecycle.
October 24, 2026Chaos Engineering Basics
Chaos engineering is controlled experiments that inject failure to verify your system tolerates it. Here's the method, safe blast radius, starter experiments, and game days.
October 24, 2026GuardDuty and Security Hub, Explained
GuardDuty is threat detection from your AWS telemetry; Security Hub aggregates findings and runs compliance checks. Here's what each does and how to wire them to a response.
October 24, 2026CloudFront Cache Behaviors, Explained
A CloudFront distribution routes paths to origins via ordered cache behaviors. Here's the cache key model, cache vs origin-request policies, and TTL precedence.
October 24, 2026ALB vs NLB (and When to Use Each)
ALB is an L7 HTTP router with rich features; NLB is an L4 pass-through with static IPs and raw throughput. Here's the decision, feature by feature.
October 24, 2026Kubernetes Jobs and CronJobs
A Job runs pods until they succeed; a CronJob creates Jobs on a schedule. Here's parallelism, retry limits, the missed-schedule trap, and history cleanup.
October 24, 2026