Sui halts block production twice in 2 days for 9.5 hours

Consecutive service interruptions

These back-to-back outages marked two straight days of technical problems for the Sui network. The first disruption occurred on Thursday and lasted nearly six hours, traced back to a critical bug in the gas fee calculation software. The latest outage started at 11:51 UTC on Friday, when the addition of new blocks stopped abruptly. Normal operation was only reestablished after 3:30 UTC.

According to a Sui network statement, a temporary fix was implemented with a low likelihood of additional issues, while a permanent software correction has now been rolled out by most network validators.

Prior to this most recent incident, Sui had already experienced its second major outage of 2026, raising further concerns about the platform’s technical stability.

Major network error in January

At the beginning of 2026, Sui suffered another substantial disruption, where block production halted for more than six hours due to a serious consensus failure. During that episode, validators submitted conflicting transactions for approval at the same time, and consensus could not be reached to process them. A follow-up analysis highlighted that the system’s control and quarantine mechanisms were triggered, ensuring that user funds were not at risk and no processed transactions were reversed.

Glossary: A consensus failure occurs when validators on a blockchain network cannot reach agreement on the accuracy of transactions. Such errors can result in double spending, network splits, or a complete halt of operations.

The Sui team emphasized that the January outage was not triggered by network congestion. They also pointed out that the halt was handled in a way that prevented any visible chain split, even though the network stopped completely for several hours.

Impact of outages on blockchain networks

Disruptions like those seen on Sui bring renewed attention to the challenges faced by both decentralized and centralized networks. In decentralized blockchains, particularly those that aim for high scalability, a variety of complex issues can arise in day-to-day operations. Flaws may occur during data sharing among validators, the execution of transactions, or when making collective network decisions.

Centralized exchanges and service providers are not immune to such disruptions. In May, for example, crypto exchange giant Coinbase was forced to shift operations into “auction” mode and temporarily suspend user transactions due to an outage in Amazon Web Services’ infrastructure. While centralized organizations may experience fewer challenges coordinating a technical response, their dependence on external service providers can still lead to similar outages.