Sui Reveals What Caused Three Network Outages

Sui Network's core team has completed its investigation into three mainnet outages that struck the network on May 28 and 29, 2026, publishing a detailed post-incident report that traces each shutdown to specific code-level failures.

What Caused the Outages

The first two incidents shared the same root cause. Both stemmed from crash bugs involving the interaction of gas charging logic and the version 1.72 release, which had introduced an address balances feature. The initial fix deployed after the Thursday outage was an interim measure designed to restore the network quickly, though the team acknowledged it carried a low probability of triggering another halt. That risk materialised on Friday morning when a variant of the same issue caused a second stoppage.

The third outage was a separate matter. It occurred at the next scheduled epoch change on Friday afternoon, when a latent bug in how validators preserve randomness state across restarts was exposed as validators rebooted to adopt the Friday morning fix. The first outage began at roughly 7am PT and ended at around 1:30pm PT on Thursday. The second ran from approximately 5am to 8:30am PT on Friday, and the third from around 1:30pm to 7:20pm PT on Friday.

Broader Reliability Questions

During the outages, no user funds were at risk and the network did not revert any committed transactions when it resumed. Validators have since fully addressed both the gas-charging bug and the randomness-state bug, and network activity has resumed.

The events mark the third major disruption for Sui in 2026. In January, the network experienced a six-hour consensus divergence event that also required a coordinated validator response. The latest disruptions add to a string of technical issues for Sui that has faced previous outages and performance incidents since late 2024. The core team acknowledged that the incidents exposed areas requiring stronger resilience and better failure containment, with further improvements to be outlined as part of the post-mortem process.

Sources:
Sui Blog: Sui Mainnet Halts Resolved After Major Upgrade
CoinDesk: Sui Blockchain Suffers Another Network Outage