Network Incident History

A running log of substantive incidents and scheduled upgrades affecting Base Mainnet and Base Sepolia. Procedural status pings are omitted. Entries are newest first.

2026

2026-07-28 — Mainnet safe head fell behind

At 13:10 UTC on Tuesday, July 28th, the safe head on Base Mainnet was reported as lagging. Unsafe block production was unaffected — the delay was confined to the batching of L2 data down to Ethereum L1, so chain progress at the tip continued as normal. The safe head was advancing again by 15:13 UTC, when the incident was closed.

2026-07-21 — Mainnet Flashblocks websocket capacity reduced

On Tuesday, July 21st, the Flashblocks websocket stream on Base Mainnet ran at reduced capacity for roughly fifty minutes, spanning 19:50 to 20:42 UTC. Subscribers were likely to see messages arrive late over that window, and fresh connection attempts could come back rate limited. The event was marked resolved once stream capacity recovered.

2026-06-25 — Mainnet chain stall

Beginning at 16:03 UTC on Thursday, June 25th, Base Mainnet block production turned unhealthy. The team traced it to a consensus fault: an invalid block had been sequenced, which kept new blocks from being built past block 47806542. Sequencing of fresh blocks was restored by around 17:51 UTC, though ecosystem node operators had to restart their Base nodes to resume syncing. Healthy block building was confirmed shortly after, and the Beryl hardfork still activated on schedule at 18:00 UTC. By 19:22 UTC the network was stable with recovery verified across the ecosystem; any nodes still stuck at block 47806542 recover on restart. The root cause was identified and a fix put under verification, with a full post-mortem and root-cause analysis promised to the ecosystem.

2026-06-25 — Mainnet Beryl upgrade (scheduled)

Base Mainnet is scheduled to activate the Beryl hardfork on Thursday, June 25th at 18:00 UTC (Unix timestamp 1782410400). Operators of Mainnet nodes must move to the 1.1.1 release or later of github.com/base/base, with matching preconfigured binaries published as the v1.1.1 release of github.com/base/node. Migration steps are documented in the Beryl Upgrade Overview.

2026-06-18 — Sepolia Beryl upgrade (scheduled)

Base Sepolia is scheduled to activate the Beryl hardfork on Thursday, June 18th at 18:00 UTC (1781805600). Operators of Sepolia nodes need to move to the v1.1.0 release or later of github.com/base/base, with matching preconfigured builds shipped as the v1.1.0 release of github.com/base/node. The migration details live in the Beryl Upgrade Overview.

2026-06-12 — Mainnet p2p peering instability

On Friday, June 12th at 21:28 UTC, the team began investigating peering problems on Base Mainnet where newly started nodes were having trouble finding peers. As a temporary measure, affected operators were pointed at a short list of --trusted-peers enode entries to add to their Reth node and restart while a fix was developed.

2026-06-02 — Mainnet Flashblocks broadcasting degraded

On Tuesday, June 2nd at 22:32 UTC, the team began investigating periodic instability in Flashblocks broadcasting on Base Mainnet. Pre-confirmation delivery was affected, but transaction inclusion in sealed blocks was reported as unaffected throughout.

2026-05-29 — Mainnet withdrawal delay (TEE enclave)

On Friday, May 29th at 15:55 UTC, Base Mainnet withdrawals began running late after a TEE enclave fault stopped output proposals from being posted. The issue was identified and a fix was reported in progress; withdrawals resume once proposals catch back up.

2026-05-28 — Mainnet Azul upgrade (scheduled)

Base Mainnet activates the Azul hardfork on Thursday, May 28th at 18:00 UTC. Node operators must run version 0.9.0 or later of github.com/base/base, with corresponding preconfigured binaries published as the v0.16.0 release of github.com/base/node. From this upgrade onward, base-consensus and base-reth-node are the only supported clients — op-node and op-geth will not follow the new chain. Pending withdrawals will be invalidated by the upgrade; users with in-flight withdrawals will need to submit a second proof transaction afterward to complete them. Migration steps are documented in Base v1 upgrade.