Availability
Everything on SkillVeris tagged Availability — collected across the glossary, study notes, blog, and cheat sheets.
12 resources across 2 libraries
Study Notes(6)
High Availability Basics
Core SQL Server high-availability options — Always On Availability Groups, Failover Cluster Instances, and log shipping — and how they differ.
PostgreSQL High Availability Patterns
Learn how to design a highly available PostgreSQL deployment combining replication, automated failover, connection routing, and backups to meet real RTO/RPO ta…
The AWS Global Infrastructure
How AWS Regions, Availability Zones, and Edge Locations are structured to deliver low-latency, fault-tolerant, and globally distributed applications.
Redis Sentinel for High Availability
How Redis Sentinel monitors a primary/replica deployment, detects failures, and orchestrates automatic failover without a cluster topology.
Cloud Regions and Availability Zones
Understand how cloud providers organize infrastructure into regions and independently-failing availability zones for fault tolerance.
High-Availability Design
Design systems that stay up through redundancy and automatic failover, and understand what each additional 'nine' of uptime really costs.
Interview Questions(6)
What is CAP Theorem?
CAP theorem states that a distributed data store can only guarantee two of three properties at once — Consistency, Availability, and Partition tolerance — duri…
What is Eventual Consistency?
Eventual consistency is a consistency model in which, if no new updates are made to a piece of data, all replicas will converge to the same value over time, th…
What is the CAP Theorem and What Trade-offs Does It Force?
The CAP theorem states that a distributed data store can provide at most two of Consistency, Availability, and Partition tolerance at the same time, and since…
What Do "Nines" of Availability Mean?
"Nines" of availability refer to the percentage of time a system is operational, expressed as a count of 9s — three nines (99.9%) allows about 8.77 hours of do…
What is Multi-Master Replication?
Multi-master replication is a topology where two or more nodes can each independently accept writes and replicate them to one another, unlike single-leader rep…
What Are Network Partitions in Distributed Systems?
A network partition occurs when a communication failure splits a distributed system into two or more groups of nodes that can no longer reach each other, even…