Azure Storage holds the blobs, disks, files, and queues underneath almost everything else - VMs boot from it, databases persist to it, and platform services depend on it. Storage rarely fails everywhere at once; incidents typically hit a set of storage scale units in one zone or region, which is exactly how the July 2024 Central US outage cascaded into VMs and Microsoft 365.
Storage scale-unit unavailability in one availability zone, taking dependent VMs down with it
Elevated error rates or latency on blob read/write in one region
Managed-disk I/O degradation making VMs slow rather than down
Configuration or allowlist errors blocking access to otherwise-healthy storage (the July 2024 pattern)
Azure Storage questions
Is Azure Storage down right now?+
The live pill above reflects our latest check. Because Storage sits under so many services, an incident often shows up first as VM restarts or database failovers - the blast radius is visible before the root cause.
What happened in the July 2024 Central US storage outage?+
An allowlist configuration error on Azure Storage scale units made storage unavailable across an availability zone in Central US, taking down Virtual Machines and dependent services - including Microsoft 365 - for many hours. Our full post-mortem covers the timeline and lessons.
Does Azure Storage downtime qualify for SLA credits?+
Yes - read-access geo-redundant storage carries up to a 99.99% read SLA and locally-redundant storage 99.9%; falling below pays tiered credits (10–25% and up) on claim through Azure support.
Get alerted when Azure Storage breaks
Instant email the moment we detect an incident - affected services and regions included.
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