# Yandex says Sasovo data center is shut; part of Kaluga site is offline > Yandex says Sasovo is shut after an October 7 to 8 attack and part of its Kaluga data center is out of service after an October 9 attack. Reuters reports two AI supercomputers were housed at Sasovo; their current status is unknown. By BIG CHANGE Editorial Published: 2026-10-10T09:59:57.036Z Updated: 2026-10-10T09:59:57.036Z Canonical: https://bigchange.ai/blog/yandex-sasovo-kaluga-data-center-outages ![Illustration of two generic server-rack banks in a data-center aisle, one unlit and one partly lit.](https://bigchange.ai/api/media/file/yandex-data-center-outages-hero-v1.png) Conceptual AI-generated illustration by BIG CHANGE. The generic server racks do not depict Sasovo, Kaluga, the reported attack, or verified equipment status. Yandex says a drone attack seriously damaged its Sasovo data center overnight from October 7 to 8, 2026, and that operations there have completely stopped. A second Yandex data center, in Kaluga, was attacked on October 9; part of its infrastructure is out of service. The company says it cannot yet estimate when equipment at the two sites will return to operation. Reuters reports that Sasovo housed two of Yandex’s three AI-development supercomputers, based on information the company disclosed in 2021. Their condition after the attack remains unconfirmed: Reuters says Yandex declined to say whether either system was affected. ## The big change - **What changed:** Two Yandex data centers suffered disruptions in successive days. Sasovo is fully shut down, while part of the Kaluga infrastructure is out of service. - **Why it matters:** Yandex says its data centers support services used by millions of people and hundreds of thousands of businesses. The reported location of two AI supercomputers also makes the facility outage relevant to model development, though their status and workload alternatives remain unreported. - **What to watch:** Yandex has not given a restoration timeline. A specific update on equipment and service recovery would show what has resumed. The status of the AI supercomputers at Sasovo is still unknown. ## What Yandex has confirmed In its October 9 statement, Yandex says the Sasovo center was seriously damaged in a drone attack during the night from October 7 to 8 and was completely shut down. It says another attack hit its Kaluga data center on the morning of October 9, leaving part of that site’s infrastructure out of service. The company said no employees were injured at either location and that emergency responders and Yandex specialists were working on site. Yandex has not published a count of damaged servers or identified the services that rely on the affected equipment. The company says it is still assessing its infrastructure and cannot yet estimate when equipment at the data centers will be operating again. The duration and full reach of the disruption remain unresolved. Yandex describes its data centers as critical to consumer services and to technology used by hundreds of thousands of companies. It says its teams are working to keep services running and help affected users and customers. The October 9 notice does not quantify the capacity still available or give a recovery rate. ## What is known about the AI computers Reuters reports that Sasovo housed two of Yandex’s three AI-development supercomputers, citing information the company disclosed in 2021. Reuters says Yandex described the machines as built around Nvidia A100 chips and used to train its YandexGPT model. The report also says Yandex declined to say whether the computers were affected by the attack. The confirmed facility shutdown and the earlier description of where the supercomputers were housed establish their connection to Sasovo. Their condition, October location and accessibility remain unconfirmed. Neither source reports a pause in YandexGPT training or a delay to model development. The incident makes the location of AI computing infrastructure relevant to the recovery story, while leaving the equipment’s condition unanswered. A site shutdown establishes that the facility is unavailable. Information about individual systems or workloads would require a separate update from Yandex. The company has not supplied those details in the sources reviewed here. ## What this means for service continuity Yandex says keeping services running and helping affected users and customers are priorities. It acknowledges that users may face disruptions. The company and Reuters have not provided a complete service-by-service outage list, a measured customer impact, or a timeline for restoring equipment. The public information about cloud customers is limited. Yandex’s October 9 notice does not identify affected customer workloads, storage systems or locations. Reuters reports that the owner of a startup with 8,000 users said none could access its app since October 8 and that his company could not reach its backup database in Yandex Cloud. He said the company had no confirmation of data loss. Reuters describes one customer’s experience and provides no measure of disruption across Yandex’s wider customer base. A useful recovery update would identify which infrastructure is back, which services remain affected and when equipment restoration can be estimated. Until Yandex provides those details, claims about damage to its AI systems or outcomes for particular customers go beyond the available evidence. ## Sources & further reading - [Yandex: “What is happening to our data centers, the iron heart of Yandex” (October 9, 2026)](https://yandex.com/company/news/2026-10-09). The company’s account of the Sasovo shutdown, the Kaluga outage, employee safety, its service-continuity response and the unknown restoration timing. - [Reuters: “Ukraine hits second major tech site, expanding range of targets inside Russia” (October 9, 2026)](https://www.investing.com/news/economic-indicators/ukraine-expands-drone-strikes-on-data-centres-owned-by-russias-yandex-4940686). Independent reporting on both facilities and the earlier Yandex disclosure that Sasovo housed two AI-development supercomputers. Reuters also reports that Yandex declined to say whether they were affected. ## Sources - [Yandex: What is happening to our data centers, the iron heart of Yandex (October 9, 2026)](https://yandex.com/company/news/2026-10-09) — Primary company statement confirming damage and downtime. - [Reuters: Ukraine hits second major tech site, expanding range of targets inside Russia (October 9, 2026)](https://www.investing.com/news/economic-indicators/ukraine-expands-drone-strikes-on-data-centres-owned-by-russias-yandex-4940686) — Independent reporting; AI compute location based on prior company disclosure and system status unconfirmed.