Ukrainian drones knock out three Yandex data centers in four days, disrupting Russia's largest cloud

Yandex said on Sunday that a drone attack had completely shut down its data center in the Vladimir region. It is the third major Yandex facility taken offline since October 8. On the night of October 7 to 8, a drone strike started a fire at the company's site in Sasovo, in the Ryazan region, and that site has stopped operating entirely. A strike on Kaluga on October 9 disabled several modules there. According to Meduza, the Sasovo hub held tens of thousands of servers and two of Yandex's A100-based supercomputers, which the company uses to train its YandexGPT models.

The outage reached developers directly. The Ukrainian outlet UNN reported that more than 80 Yandex Cloud services failed, among them compute, managed databases, storage and the YandexGPT API. Russian-language reports covered the same failures. Cloudflare Radar data shared on Hacker News shows bot traffic from Yandex's autonomous system down about 99 percent over the past week. That drop implies the company's search crawler has largely stopped running.

A widely read Russian AI channel explained why recovery is slow. Restoring service after several large data centers are damaged at once is much harder than shifting load to backup servers, the channel wrote, because Yandex's components are tightly coupled and serve millions of users. The underlying problem is familiar to engineers: geo-redundancy plans usually assume that one region fails. They rarely assume that three sites fail within a few days. The Moscow Times reported that the first strike came after a wave of Russian attacks on Ukraine. Ukrainian outlets such as United24 describe the campaign as a deliberate effort to target Russian digital infrastructure. Russian officials have not publicly explained the targeting, and claims from either side in wartime deserve caution.