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126 questions, 454 terms and 400 topics in 20 areas.
15 results for “Failover”
Active-Active vs Active-Passive
Whether all regions serve traffic simultaneously, or one serves while another waits to take over — a choice about which failure mode you would rather have.
DNS
The distributed directory that resolves names to addresses, and a surprisingly load-bearing part of most architectures.
Failback
Returning to the primary region after a failover, including reconciling the data written while it was unavailable — the half of DR that is usually unplanned.
Global Traffic Management
The layer that decides which region a given user reaches, using DNS, anycast or an edge network, and that performs regional failover.
Managed Service
A capability the provider operates — provisioning, patching, backup, scaling and failover — leaving you the configuration and the data.
Managed Service Upgrade Window
The period during which a provider may apply patches or version upgrades to a managed service, usually involving a failover or brief unavailability.
Pilot Light
A disaster recovery posture where core data is continuously replicated and minimal infrastructure runs, with the rest provisioned only on failover.
Redundancy
Having more instances of a component than the load requires, so that failures can be absorbed without loss of service.
Regional Evacuation
The deliberate, rehearsed act of shifting all traffic out of a region — treated as a routine operation rather than an emergency procedure.
Slack's Cellular Migration
After repeated availability-zone-level incidents, Slack rebuilt its infrastructure into per-zone cells with the ability to drain traffic away from a failing zone in minutes.
Split Brain
A partition in which two halves of a cluster each believe they are authoritative, and both accept writes.
A 43-second network partition caused GitHub over 24 hours of degraded service in 2018. How does a 43-second event become a day-long incident?
The case, as publicly reported On 21 October 2018, routine maintenance replacing failing optical equipment caused a 43 second loss of connectivity between GitHu
Your cluster fails over spuriously under load, but a real leader failure takes 45 seconds to detect. How do you resolve the tension?
The tension Detection time is set by the heartbeat interval times the failure threshold. Shorten it and you detect real failures faster and mistake slow but ali