Intermediate concepts in DevOps & Cloud, page 3
Cloud Storage Tiers: Match Cost to Access Frequency
Storage tiers match data cost to access frequency. 'Hot' tiers are fast and expensive for active files; 'cold' tiers are cheap for archives. Use for data that cools over time, like logs. The footgun: retrieving cold data unexpectedly is slow and costly.
Apache Maven: Convention Over Configuration for Builds
Maven standardizes your build process using a 'convention over configuration' model, defining project structure and dependencies declaratively. It's the backbone of many Java projects, ensuring consistent builds. The footgun is fighting its conventions.
OpenTelemetry Collector: The Swiss Army Knife for Telemetry Data
The OpenTelemetry Collector is a universal adapter for your telemetry data. It receives data in one format, processes it, and exports it to multiple backends, letting you centralize configuration and avoid vendor lock-in.
Block Storage Snapshots Are Incremental Backups
A snapshot is an incremental, point-in-time backup of a disk volume, saving only changed data blocks. Use it for disaster recovery to restore a volume's exact state. The footgun: deleting an older snapshot may not save money if a newer one needs its data.
Gradle: Code-Based Builds, Not XML
Gradle treats your build process like code, not configuration, using a flexible Groovy or Kotlin DSL instead of rigid XML. It's used for compiling and packaging multi-language projects.
Span: The Building Block of a Distributed Trace
A Span is a single unit of work in a request's journey, like one leg of a flight. Spans capture the duration and context of individual operations (e.g., a DB query), helping you debug latency in distributed systems.
Cross-Region Replication (CRR): Geographic Data Copying
Cross-Region Replication automatically copies data to another geographic region, like a live backup. Use it for disaster recovery, lower latency for global users, or compliance. The footgun: it only copies *new* objects, not what's already in the bucket.
Maven's Build Lifecycle: A Sequence of Build Phases
Maven's build lifecycle is a predefined sequence of phases like compile, test, and package. Running a phase executes all preceding ones, ensuring a consistent build.
OpenTelemetry Semantic Conventions: A Shared Vocabulary
Think of Semantic Conventions as a universal dictionary for telemetry. They standardize attribute names like http.method across all services, letting you correlate data from different languages, libraries, and platforms seamlessly.
Encryption at Rest: Securing Your Data When It's Not Moving
Encryption at rest is like locking your data in a safe when it's not moving. It protects raw files on disk if storage is stolen, a default on platforms like Google Cloud. The footgun: it doesn't stop a compromised app with valid keys from reading.
Code Coverage: What Your Tests Don't Tell You
Code coverage measures which lines of code your tests execute, not how well they're tested. It's used in CI to enforce a testing baseline, but the footgun is mistaking high coverage for high quality—100% coverage can exist with zero useful assertions.
OpenTelemetry Protocol (OTLP): The Universal Adapter for Telemetry
OTLP is the universal adapter for observability, providing a single vendor-neutral protocol for traces, metrics, and logs. Use it to send data from an OpenTelemetry SDK to a collector.
OpenTelemetry Resource: The 'Who' of Your Telemetry
An OpenTelemetry Resource is the return address for your telemetry, describing the service instance that produced it. It attaches stable context like service name and version to every signal, enabling filtering.
Amazon EC2: Rentable Virtual Servers on AWS
Amazon EC2 is like renting virtual computers, letting you run applications without buying physical hardware. It's used for scalable deployments where you can launch and terminate servers as needed, paying only for what you use.
Artifact Registry: Google's Universal Package Manager
Artifact Registry is a private, universal package manager for all your software components, not just Docker images. Use it to store your company's Docker images, Java JARs, and Helm charts in one place, integrated with GCP CI/CD.
Image Digest: The Immutable Image Identifier
An image digest is a unique fingerprint for a container image, guaranteeing you get the exact version you expect. Use it in production to pin an image, preventing unexpected updates from mutable tags like :latest. The footgun is assuming a tag is immutable.
Quality Gates: Your Automated Code Quality Checklist
A quality gate is an automated checklist that asks, 'Is this code ready to release?' It runs in CI/CD to enforce standards on metrics like bugs and test coverage, blocking merges that fail. The footgun is using one gate for all projects; tailor rules to.
Docker Registry Mirror: A Local Cache for Faster Pulls
A registry mirror is like a CDN for Docker images, caching public images on your local network to speed up pulls and avoid rate limits. Use it in CI/CD pipelines to reduce build times. The footgun: you can't docker push to a mirror; it's a.
Regression Testing: Don't Break What's Already Working
Regression testing asks: 'Did my new code break old features?' It's re-running existing tests after a change to catch unintended side effects. It's crucial in CI/CD pipelines before deploying. The footgun is a slow suite that developers skip.
Elasticsearch: The Search Engine in the ELK Stack
Elasticsearch is a distributed search engine for querying massive, schema-free JSON datasets via an HTTP API. It's the core of log analysis platforms like the ELK stack, enabling fast search over terabytes of logs.
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