Base2026-06-28 01:09:20Base Mainnet Postmortem: Sequencer State Management Bug Causes Two Block Production OutagesBase experienced two block production outages on June 25 and 26, 2026, lasting approximately 116 minutes and 20 minutes respectively. The official postmortem report identifies the root cause as a sequencer state management bug: after a failed transaction execution, the system failed to clean up historical journal state, leading to anomalous gas calculation and invalid state transition blocks. Base has deployed fix PR #3806 and plans to enhance fuzzing, stress testing, and recovery mechanisms. User funds remained safe throughout.590
Base2026-06-28 01:09:20Base Mainnet Outage Postmortem: Sequencer State Management Bug Halts Block Production, Official Vows Enhanced Testing and RecoveryBase has released a postmortem report on two consecutive block production outages on its mainnet on June 25 and 26, lasting approximately 116 minutes and 20 minutes respectively. The incidents did not compromise on-chain asset security, and user funds remained safe throughout. The root cause was identified as a bug in the sequencer's block construction logic: after a transaction execution failure, the system failed to properly clean up the historical journal state, leading to incorrect gas calculations for subsequent valid transactions and generating invalid state transition blocks. This ultimately halted block production on the L2 network. A patch (PR #3806) was deployed to fix the issue, but a race condition during the sequencer cluster restart contributed to a brief recurrence the next day. Going forward, Base plans to strengthen protocol-level fuzz testing and stress testing, as well as introduce a graceful recovery mechanism to improve resilience against similar failures.640
