Yandex reports second data-centre strike as recovery questions remain

Yandex said Ukrainian drones partly disabled its data centre in Russia’s Kaluga region, southwest of Moscow, on October 9, a day after an attack shut down its Sasovo hub. The successive strikes threaten infrastructure supporting everyday digital services and artificial intelligence, although the extent of disruption and equipment damage remains unclear, Reuters reported.

The company said it was assessing damage at Sasovo, in the Ryazan region, and could not confirm whether equipment could be restored. It declined to say whether supercomputers housed there were affected. The shutdown therefore does not establish that those machines were destroyed.

What Yandex says about service disruption

According to the Reuters report published by CNA, Yandex operates five data centres. Two have now been hit; of the other three, two are in the Moscow region and one is in the Vladimir region. The report did not quantify spare capacity at the remaining facilities.

“Data centers are the iron heart of Yandex,” the company said in a statement quoted by Reuters. It said millions of users depend on its services to check traffic, plan routes, listen to music, watch films, order groceries and find answers to questions.

Reuters reported warnings of potential operating problems on at least one Yandex application. Yandex said it was working around the clock to restore disrupted services, but the report provided no firm recovery deadline or comprehensive measure of the outage.

Why the Sasovo hub matters for AI

Yandex’s November 2021 supercomputer announcement placed two systems, Chervonenkis and Lyapunov, at Sasovo and a third, Galushkin, in Vladimir. The company described machines built around AMD EPYC processors and NVIDIA A100 accelerators. Those historical specifications establish the site’s computing role, not the condition of its equipment after the strikes.

The company said the systems trained neural models with billions of parameters, with some training requiring days or weeks at peak power. It identified applications in translation, advertising, search answers and its Alice assistant, showing how the infrastructure supported more than website hosting.

The independent TOP500 listing records Chervonenkis achieving 21.53 petaflops in the Linpack benchmark, compared with a theoretical peak of 29.42 petaflops. It ranked 19th worldwide in November 2021 and 101st in June 2026. These pre-strike records do not measure current availability or establish how much AI-training capacity Yandex has lost.

Shares fall as analysts assess business exposure

Yandex shares were down 3.75 percent and were the biggest faller on the Moscow exchange at the point reported by Reuters. That was a trading snapshot, rather than an established closing price or a valuation of the physical damage.

Maryana Lazaricheva, head of equity research at T-Investments, told Reuters that risks included temporary service unavailability, lost revenue in individual business segments and exposure across Yandex’s business-customer base. These were prospective risks; the report did not establish quantified financial losses.

Lazaricheva said Yandex could redistribute some workload to other data centres, but warned that continuing attacks could remove that option and worsen the consequences. Her assessment did not establish how much capacity was available or whether redistribution had succeeded.

Data centres become targets in reciprocal strikes

Reuters reported that Russia had struck Ukrainian data centres and telecommunications infrastructure over the preceding month, including targets in central Kyiv. On October 8, Ukrainian President Volodymyr Zelenskiy linked Ukraine’s response to those attacks, saying: “We always respond in mirror-like fashion.” He declined to disclose all the details.

Technical problems were also reported on October 8 at property aggregator Cian, book portal Litmarket and the websites of Russian Railways and football club Spartak Moscow. Reuters did not establish a separate technical cause for each problem or show that all resulted from the Sasovo strike.

Yandex’s immediate stated priority is restoring disrupted services. Its damage assessment leaves material questions unanswered: which equipment can be recovered, how many customers have been affected and how long restoration will take. The company’s historical computing inventory cannot resolve those operational questions.