Step-by-step articles on Infrastructure, part of our Cloud & DevOps collection.
Showing 20 articles
Clicking around a cloud console is fine once. For anything you need to repeat, review or recover, describe infrastructure in code. Terraform reads configuration files and creates, updates or deletes cloud resources to match. A first configuration # main.tf ter...
Monitoring tells you that something is wrong. Observability helps you understand why , including for problems you didn't predict. It's built from three kinds of telemetry. Metrics: numbers over time http_requests_total{route="/checkout", status="500"} 1243 htt...
The state file is Terraform's memory: which real resources belong to which blocks in your code. For a team, it must be shared, locked during changes and protected, because it can contain secrets. An S3 backend with locking terraform { backend "s3" { bucket = "...
OpenTelemetry's auto-instrumentation patches popular libraries (http, Express, pg, Redis, fetch and many more) so you get traces with almost no code changes. Zero-code setup npm install @opentelemetry/api @opentelemetry/auto-instrumentations-node export OTEL_S...
Hard-coded values make Terraform code impossible to reuse. Variables bring values in, locals compute values once, and outputs send values out. Input variables # variables.tf variable "environment" { type = string description = "Deployment environment" validati...
In a system of many services, one slow user request might pass through an API gateway, three services, a queue, two databases and a third-party API. Distributed tracing reconstructs that whole path. Traces and spans A trace is the full journey of one request,...
A module is a folder of Terraform files used as a building block. Good modules capture your organisation's standards (encryption on, tags set, sensible defaults) so every team gets them for free. Module layout modules/static-site/ main.tf # resources variables...
console.log("user " + id + " failed") is fine on a laptop. In production you need logs that machines can search and filter: JSON with consistent fields, levels and request IDs. Basic setup import pino from 'pino'; export const logger = pino({ level: process.en...
Almost every project needs the same infrastructure in several environments, with small differences: smaller instances in dev, more replicas in prod. There are three common approaches. 1. Separate directories (most common) infra/ modules/ app/ # the shared buil...
Prometheus is the most widely used open-source metrics system. Your app exposes current values on a /metrics endpoint, and Prometheus scrapes them every few seconds and stores them as time series. The metric types Counter - only goes up (resets on restart): re...
Most teams adopt Terraform after resources already exist. Recreating them isn't an option, so you import them: tell Terraform that an existing resource belongs to a block in your code. Import blocks # imports.tf import { to = aws_s3_bucket.uploads id = "acme-s...
You can measure thousands of things. These three well-known frameworks tell you which handful matter most. The four golden signals From Google's SRE book, for any user-facing system: Latency - how long requests take. Track successful and failed requests separa...
Terraform identifies resources by their address, like aws_s3_bucket.assets . Rename it in code and Terraform plans to destroy the old one and create a new one, which for a database is a disaster. moved and removed blocks tell Terraform what you really meant. R...
"Make it reliable" isn't a goal you can measure. Service level objectives turn reliability into a number that product and engineering can agree on. The terms SLI (indicator) - a measurement of user experience, usually a ratio of good events to total events. Ex...
Running terraform apply from laptops leads to "who changed this?" moments and state conflicts. A CI workflow makes every change visible, reviewed and repeatable. The flow A pull request changes Terraform code. CI runs fmt , validate and plan , and shows the pl...
Apps can send telemetry straight to a vendor, but most production setups put an OpenTelemetry Collector in between. It receives data from many sources, processes it and exports it to one or more backends. Why use a Collector Apps only need to know one endpoint...
In 2023 HashiCorp changed Terraform's licence from the open-source MPL 2.0 to the Business Source License (BSL). In response, a group of companies forked the last open-source version as OpenTofu , now a Linux Foundation project. What's the same The HCL languag...
When alerts fire constantly, people stop reading them, and the one that matters gets missed. Good alerting is mostly about deciding what not to page on. 1. Every page must be urgent and actionable Ask: "If this fires at 3 a.m., does someone need to do somethin...
Modules are code that many teams depend on, so they deserve tests. Terraform includes a test framework: .tftest.hcl files with runs and assertions. A plan-only test # tests/naming.tftest.hcl variables { environment = "staging" domain = "shop.example.com" } run...
LLM features fail in new ways: answers get worse without any error, costs spike because a prompt grew, an agent loops through tools. Normal API monitoring doesn't catch these, so add LLM-specific telemetry. 1. Usage and cost const response = await client.messa...
