Yandex Says 2.84% of Cloud Customer Data Cannot Be Restored

Yandex says it has restored access to 97.16% of Yandex Cloud customer data after attacks on its data centres, and that the rest cannot be brought back. In a company statement dated 10 November 2026, it said engineers “were able to restore access to 97.16% of customer data in Yandex Cloud. The remaining 2.84% cannot be restored because of critical damage to equipment and the absence of customer backups on the platform.” The Yandex Cloud blog, published the same day, repeats those figures and adds the operational changes that now sit around them.

The useful lesson is about backups, not about the attack method. Yandex’s own pages say only that data-centre infrastructure “was damaged” in October, and that the unrestorable slice is the data that had no platform backup. Customers who had used Yandex Cloud’s own backup tools, the company says, “lost no data” — “all 100%” was kept. Those tools, the blog lists, are Object Storage, Cloud Backup, disk snapshots and the standard backups of managed databases.

Backups are now on by default for new virtual machines, and a new zone is opening with tight quotas

Yandex Cloud says it has changed how new machines are created. Previously, customers had to switch backup on themselves. “Now, when new virtual machines are created, it is enabled by default.” Customers “can turn it off themselves in the management console.” The company news post says the service remains available “on the previous terms,” and that declining the backup is still possible, but that it “remains the basic way to reduce risks in unforeseen circumstances.”

The same 10 November blog says a new availability zone, ru-central1-f, “in a new location,” launches on 11 November, “to improve the fault tolerance of customers’ services.” At the start, it comes with limits. “Getting resources will be limited by quotas,” which customers can ask to raise through support. Local disks in managed-database clusters will be available on standard-v3 platforms in all services except Yandex Managed Service for ClickHouse and Yandex MPP Analytics Engine for PostgreSQL, “temporarily.” Private Endpoints can be created in the new zone, but their traffic “will be served by other availability zones” until a local traffic-processing cluster is ready. Engineers, the company news post adds, are still spreading compute “across new independent locations in different regions of the Russian Federation.”

Those are company claims about a restoration and a rebuild. Yandex has not published a count of affected customers, and it has not broken the 2.84% down by service.

The customers who kept everything were the ones who already had a platform copy

The restoration arithmetic is stark enough without dressing it up. Almost all of the data came back. The slice that did not, Yandex says, failed for two reasons at once: equipment was critically damaged, and those customers had no backup on the platform. The customers who had used the platform’s own backup products kept a complete copy. The company’s response is to make that backup the default for new virtual machines, while still allowing it to be switched off.

That is a resilience story, and it should be read as one. TSN’s earlier report on the October disruption at Yandex data centres covered the incident when Yandex Cloud was in limited mode. This follow-up is the first official accounting of how much data came back. It also sits beside Russia’s decree on data-centre capacity, which is about national infrastructure policy, and beside TSN’s account of physical damage at a Sberbank data centre in Balakovo, another reminder that a data centre’s risk is not only in software. Yandex itself does not name an attacker in the 10 November notices, and this post follows that wording.

The next test is practical: whether customers actually leave the new default backup on, and whether ru-central1-f’s early quotas and missing local services are loosened on a published timetable. The 11 November launch is the date Yandex set. The 2.84% figure is the one it says will not move.

Sources

1. Yandex, company news, 10 November 2026. https://yandex.ru/company/news/10-11-2026-01
2. Yandex Cloud, “Restored access to more than 97% of customer data and launched a new availability zone,” 10 November 2026. https://yandex.cloud/ru/blog/recovery

Related stories

Drone Strikes on Three Yandex Datacenters Leave Yandex Cloud in “Limited Mode” is TSN’s account of the October disruption, the incident this 10 November restoration report follows.

Also relevant:

• Russia Data-Centre Capacity Decree
• Ukrainian Drones Hit Sberbank Data Centre in Balakovo