#reliability

Articles tagged "reliability".

17 articles

SLA vs SLO vs SLI: the reliability promise, decoded
Reliability

SLA vs SLO vs SLI: the reliability promise, decoded

Three little acronyms quietly run every serious reliability conversation — and almost everyone mixes them up. Here's what SLA, SLO and SLI actually mean, how they fit together, and how to set ones that won't page you at 3am for nothing.

WatchFor Team
8 min read
What is 99.9% Uptime? The downtime hiding behind the nines
Monitoring

What is 99.9% Uptime? The downtime hiding behind the nines

“99.9% uptime” sounds almost perfect — until you do the maths. Here's exactly how much downtime each level of nines allows, how it's calculated, and how to pick a target you can actually hit.

WatchFor Team
3 min read
Website Downtime: the most common causes (and how to prevent each)
Monitoring

Website Downtime: the most common causes (and how to prevent each)

Most outages aren't mysterious — they come from the same short list of causes, again and again. Here's that list, what each one looks like, and how to stop it taking your site down.

WatchFor Team
4 min read
Incident Metrics Explained: MTTR, MTTD, MTBF and friends
Reliability

Incident Metrics Explained: MTTR, MTTD, MTBF and friends

MTTR, MTTD, MTBF, MTTA — the alphabet soup of incident metrics, explained in plain English. What each measures, how to calculate it, and how to actually improve the numbers.

WatchFor Team
3 min read
Latency & Percentiles: why p99 matters more than the average
Performance

Latency & Percentiles: why p99 matters more than the average

Your average response time looks great — so why are users complaining? Because averages lie. Here's why percentiles like p95 and p99 tell the real story of how your service feels.

WatchFor Team
3 min read
Rate Limiting & HTTP 429 Explained
Monitoring

Rate Limiting & HTTP 429 Explained

Rate limiting is how services protect themselves from too many requests — and HTTP 429 is how they say 'slow down'. Here's how it works, and how to handle it gracefully on both sides.

WatchFor Team
3 min read
Disaster Recovery: RTO vs RPO explained
Reliability

Disaster Recovery: RTO vs RPO explained

When the worst happens, two numbers decide how bad it really is: how much data you lose, and how long you're down. Here's what RTO and RPO mean, and how to set targets you can actually meet.

WatchFor Team
3 min read
What is SRE? Site Reliability Engineering, explained
Reliability

What is SRE? Site Reliability Engineering, explained

SRE is what you get when you treat reliability as an engineering problem instead of a firefighting one. Here's what Site Reliability Engineering actually means, its core ideas, and how it differs from DevOps.

WatchFor Team
3 min read
Load Balancing Explained
Networking

Load Balancing Explained

A load balancer spreads traffic across many servers so no single one gets overwhelmed — and quietly routes around the ones that fail. Here's how it works and why it's the backbone of scalable, reliable sites.

WatchFor Team
3 min read
What is a DDoS Attack? (and how to defend against one)
Security

What is a DDoS Attack? (and how to defend against one)

A DDoS attack drowns your service in traffic from thousands of sources until it buckles. Here's how these attacks work, the main types, and the practical layers of defence.

WatchFor Team
3 min read
Error Budgets Explained
Reliability

Error Budgets Explained

An error budget turns the endless 'ship fast vs stay stable' fight into a single number both sides can see. Here's what it is, how to calculate it, and how it changes the way teams work.

WatchFor Team
3 min read
Chaos Engineering Explained
Reliability

Chaos Engineering Explained

Chaos engineering means deliberately breaking your own systems — in a controlled way — to find weaknesses before real failures do. Here's the idea, the method, and why it makes you more resilient.

WatchFor Team
3 min read
Capacity Planning Basics
Reliability

Capacity Planning Basics

Run out of capacity at the wrong moment and your big day becomes an outage. Capacity planning is how you have the headroom before you need it. Here's the simple version.

WatchFor Team
3 min read
High Availability Explained
Reliability

High Availability Explained

High availability means designing so that one failure isn't an outage. Here's what HA actually means, the building blocks (redundancy, failover, no single point of failure), and how far to take it.

WatchFor Team
3 min read
Feature Flags Explained
DevOps

Feature Flags Explained

Feature flags let you turn functionality on and off at runtime — shipping code safely, releasing gradually, and rolling back instantly without a deploy. Here's how they work and why teams love them.

WatchFor Team
3 min read
Canary vs Blue-Green Deployments
DevOps

Canary vs Blue-Green Deployments

Two popular strategies for shipping without downtime — and without betting the whole site on a release working. Here's how canary and blue-green deployments differ, and when to use each.

WatchFor Team
3 min read
Infrastructure as Code Explained
DevOps

Infrastructure as Code Explained

Infrastructure as Code means defining your servers and cloud resources in version-controlled files instead of clicking through dashboards. Here's what it is and why it transforms reliability.

WatchFor Team
3 min read