Cian

Yandex Cloud Cascade Failure October 2026 Exposes Multi-AZ Limits and Capacity Exhaustion Risks

In October 2026, Yandex Cloud suffered a prolonged cascade outage across multiple data centers in Sасово, Калуга, and Владимир, triggered by power failures and a drone-related fire that fully disabled the ru-central1-b zone. The incident revealed that standard Multi-AZ designs reach physical capacity exhaustion when multiple zones fail simultaneously, leaving insufficient resources in remaining zones for automatic failover. Businesses relying on managed Kubernetes, databases, and SaaS platforms such as Salebot and CIAN experienced extended recovery times, with backups becoming inaccessible and RTO stretching beyond 24 hours due to index rebuilds and manual quota allocation. Yandex Cloud responded by manually distributing quotas, partnering with Selectel, K2Cloud, and VK Cloud for emergency capacity, and advising clients to activate external disaster recovery plans. The outage also highlighted single points of failure in DDoS protection configurations and Control Plane dependencies that prevented timely migration of master nodes. Architectural recommendations include deploying independent edge webhook buffers using FastAPI on separate VDS instances to preserve incoming events during primary backend failures. Overall, the events underscore the necessity of true multi-cloud strategies that avoid reliance on any single provider's IAM, billing, and physical infrastructure.

Russian Internet Services Hit by Outages After Drone Attack on Yandex Data Center in Sasovo

On October 8, multiple Russian websites and internal corporate systems experienced significant disruptions. Users reported issues accessing media outlets, transport services, and marketplaces, with many problems affecting internal company tools and professional platforms. Cian linked its website and app outage to an infrastructure partner incident, while developers A101, Granel, and Brusnika also faced temporary unavailability. T-Bank reported problems with its corporate messenger and email distributions, and similar internal system issues appeared at Ozon, Wildberries, and HSE. Astral warned of possible delays in electronic reporting and document management services. Yandex confirmed a fire at its Sasovo data center in Ryazan region following a drone attack, with no casualties but full shutdown of the facility. Experts note that not all complaints can be attributed to a single event due to varying scales of impact across companies.