Base Outage History

Started Oct 09, 2026, 01:48 PM UTC· resolved Oct 09, 2026, 07:15 PM UTC

1. investigating Oct 09, 2026, 01:48 PM UTC

   The team is investigating the proposal stall. This will slow down in-flight withdrawals.

2. investigating Oct 09, 2026, 01:48 PM UTC

   We are continuing to investigate this issue.

3. monitoring Oct 09, 2026, 02:21 PM UTC

   We've identified the issue and proposals have resumed.

4. resolved Oct 09, 2026, 07:15 PM UTC

   This incident has been resolved.

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Started Jul 28, 2026, 01:10 PM UTC· resolved Jul 28, 2026, 03:13 PM UTC

1. identified Jul 28, 2026, 01:10 PM UTC

   Base Mainnet's Safe head is delayed. New block production is progressing normally; this incident affects only data batching to Ethereum L1.

2. resolved Jul 28, 2026, 03:13 PM UTC

   Safe head is progressing normally

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Started Jul 21, 2026, 07:30 PM UTC· resolved Jul 21, 2026, 07:30 PM UTC

1. resolved Jul 21, 2026, 08:54 PM UTC

   Between UTC 19:50 and 20:42, Base Mainnet experienced reduced capacity on the Flashblocks websocket stream. Clients likely experienced delays in receiving messages and rate limits when connecting.

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Started Jun 25, 2026, 04:03 PM UTC· resolved Jun 26, 2026, 08:03 PM UTC

1. investigating Jun 25, 2026, 04:03 PM UTC

   Base mainnet block production is currently unhealthy. We're investigating the issue now.

2. investigating Jun 25, 2026, 04:24 PM UTC

   We are continuing to investigate this issue.

3. identified Jun 25, 2026, 04:52 PM UTC

   We have identified the issue with a problematic block interfering with subsequent block building. The team is working on several threads to remediate and we will continue to post updates as soon as we have them.

4. identified Jun 25, 2026, 05:21 PM UTC

   We continue to debug and have isolated a consensus problem that caused an invalid block to be sequenced. This prevented new blocks from being created following block 47806542. Internal sequencer and nodes have preliminarily recovered, the team is working on a fix to resume block propagation to the network while further isolating the root cause of the problematic block.

5. identified Jun 25, 2026, 05:51 PM UTC

   Sequencing of new blocks has resumed and internal nodes are syncing correctly. We continue to investigate the root cause while monitoring internal nodes for stability. For ecosystem node runners - *Base nodes will need to be restarted to recover syncing*. We will continue to investigate and provide updates as we have them.

6. monitoring Jun 25, 2026, 05:58 PM UTC

   We have recovered healthy blockbuilding and confirmed that ecosystem-wide infrastructure is able to recover syncing. We continue monitoring to ensure stability. Notably, we expect the Beryl hardfork to activate as planned at 18:00 UTC. We will continue to investigate the root cause and share a full post-mortem once our investigation concludes.

7. monitoring Jun 25, 2026, 07:22 PM UTC

   Base sequencer and supporting systems remain stable, blocks are being produced normally, and we have verified widespread recovery in the ecosystem. Any remaining Base nodes that are stuck at block 47806542 will recover upon restart and syncing. The team has found the root cause for this halt and is verifying a fix to ensure it cannot recurr. We’ll share a full post mortem including RCA with the ecosystem based on our learnings and fixes as a top priority. We'll continue to monitor all systems to ensure overall network health and stability persists.

8. investigating Jun 26, 2026, 03:33 PM UTC

   Base mainnet block production is currently unhealthy. We're investigating the issue now.

9. identified Jun 26, 2026, 03:34 PM UTC

   Base Mainnet is experiencing a chain halt with the similar symptoms. We're actively working on resuming block production.

10. identified Jun 26, 2026, 03:47 PM UTC

    Block production is resumed. Node operators will need to restart their Base Mainnet nodes in order to resume syncing.

11. monitoring Jun 26, 2026, 04:11 PM UTC

    A fix has been implemented and we are monitoring the results.

12. resolved Jun 26, 2026, 08:03 PM UTC

    Block production has been succesfully progressing for Base Mainnet. A detailed postmortem will be be published to outline the technical root cause.

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Started Jun 12, 2026, 09:28 PM UTC· resolved Jun 22, 2026, 04:34 PM UTC

1. investigating Jun 12, 2026, 09:28 PM UTC

   We're aware that base mainnet has peering issues for newly started nodes and are actively working on a fix to address that. For nodes that are struggling to find peers, we recommend adding below cli args to your reth node and restart for now. ``` --trusted-peers enode://674db972a48b9cab934407c9e28c50fb3c95719272d314dd408ef82804796e06e5de6f991db4e9f33b2b0f09f1ddf3d91f59cd6b3f4b183052efc3d88455d5ac@13.221.49.63:30303?discport=30304,enode://174bcf56adbfbd8eb6fa1e680c356a495d4a4dd638ede1187846f748bf85a9a7396feb64bcd8e725509efdf85362928b71ac50ad59fd73f44aad7103c56e94ac@54.161.193.150:30303?discport=30304,enode://0d5988e13d93d7b96f89767d64445d0b03ca1ad1d7e17a19c60e0997a3bb27217d8f0fca3353abb051bf2b10b10be73d4c2250a15cc1f9e3d8dd5b770fadaf38@54.209.136.129:30303?discport=30304,enode://843e9e53a61bee5bf6f7c2739455ed61ef1056172812123a3f7d6f3f10d12f7c0dc8d7a4bda966ddd4a1d1b61d58bff5558f924b3f0ca84e9e8c0e6feb277142@98.80.147.106:30303?discport=30304,enode://3f4dba3d8b19727f942c0dd63b9d5a2c87aa5cf175bd6a86b78d7913950333382f3befc09f7c0e6af36451091f5d031b2d6db2996480b5c261812ddd76708524@3.81.131.168:30303?discport=30304,enode://3081267a138669585724beec40a422f5f2c8e7f050c5845936420e679c48b43e413106c220b6aa8cd9636042962f2b2ab02e3701f6d8d9233075061cafcfe3b6@34.203.10.78:30303?discport=30304 ```

2. identified Jun 15, 2026, 05:59 PM UTC

   If you find yourself still unable to find peers, please try to delete /$RETH_DATA_FOLDER/discovery-secret file (by default /data if you're using base/node) and restart the node.

3. resolved Jun 22, 2026, 04:34 PM UTC

   This incident has been resolved.

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Started Jun 02, 2026, 10:32 PM UTC· resolved Jun 22, 2026, 04:35 PM UTC

1. investigating Jun 02, 2026, 10:32 PM UTC

   Our team is currently investigating degraded broadcasting of Flashblocks on Base mainnet. We believe TX inclusion in final blocks is not affected.

2. resolved Jun 22, 2026, 04:35 PM UTC

   The instability has been addressed and resolved. Node operators who were affected are recommended to upgrade to v1.1.1 of base/base which contains stability improvements and bug fixes: https://github.com/base/base/releases/tag/v1.1.1

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Started May 29, 2026, 03:55 PM UTC· resolved May 31, 2026, 03:38 AM UTC

1. identified May 29, 2026, 03:55 PM UTC

   Base Mainnet withdrawals are delayed due to a TEE enclave issue that halted proposals. A fix is in progress.

2. resolved May 31, 2026, 03:38 AM UTC

   This incident has been resolved.

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Started May 13, 2026, 04:44 PM UTC· resolved May 14, 2026, 05:04 AM UTC

1. investigating May 13, 2026, 04:44 PM UTC

   Base is experiencing an elevated rate of missed blocks. Transactions sent during missed blocks are delayed until the next successful block.

2. resolved May 14, 2026, 05:04 AM UTC

   This incident has been resolved.

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Started May 10, 2026, 06:31 PM UTC· resolved May 13, 2026, 04:52 PM UTC

1. identified May 10, 2026, 06:31 PM UTC

   Latency on https://sepolia.base.org is high due to a node provider upgrade.

2. monitoring May 10, 2026, 07:03 PM UTC

   We have temporarily decreased rate limits for this endpoint to ease traffic. Latency is moving back to normal on this endpoint.

3. resolved May 13, 2026, 04:52 PM UTC

   This incident has been resolved.

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Started Apr 30, 2026, 09:14 PM UTC· resolved Jun 04, 2026, 07:42 PM UTC

1. monitoring Apr 30, 2026, 09:14 PM UTC

   There is no outage. This is preemptive in case node operators encounter peering issues. However, upcoming p2p changes may impact peer discovery for Base nodes. If your node encounters p2p issues, please use the script linked here: https://gist.github.com/meyer9/8f15028681045062d59b7521deb19822#file-add-peers-sh

2. resolved Jun 04, 2026, 07:42 PM UTC

   The migration has been completed. It can be difficult to find a peer that isn't full on peers already. We are working with the Reth team to continue improving the ability to find peers.

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Started Apr 16, 2026, 06:26 PM UTC· resolved Apr 16, 2026, 07:15 PM UTC

1. investigating Apr 16, 2026, 06:26 PM UTC

   Base Sepolia Testnet is experiencing an outage in block production. The team is actively investigating.

2. resolved Apr 16, 2026, 07:15 PM UTC

   Block production has resumed on Sepolia testnet.

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Started Apr 10, 2026, 10:54 PM UTC· resolved Apr 11, 2026, 12:45 AM UTC

1. investigating Apr 10, 2026, 10:54 PM UTC

   We are currently investigating this issue. The Sepolia safe head is current stalled. This seems to affect op-node users running with consensus-layer sync mode.

2. resolved Apr 11, 2026, 12:45 AM UTC

   This is now mitigated. Safe head is progress normally for Sepolia Testnet

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Started Apr 07, 2026, 12:37 AM UTC· resolved Apr 07, 2026, 12:55 AM UTC

1. identified Apr 07, 2026, 12:37 AM UTC

   Flashblocks is currently down for Sepolia Testnet. The team has identified the issue and is rolling out a fix.

2. resolved Apr 07, 2026, 12:55 AM UTC

   This incident has been resolved.

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Started Mar 24, 2026, 12:00 PM UTC· resolved Apr 01, 2026, 01:41 PM UTC

1. investigating Mar 24, 2026, 12:00 PM UTC

   Base Mainnet is currently not producing flashblocks. Normal block production is unaffected. We're actively working to restore flashblock production.

2. identified Mar 24, 2026, 01:55 PM UTC

   We've identified an issue in our public RPC nodes that caused certain endpoints to not reflect latest flashblock data. Users may have also experienced increased error rates for read endpoints on https://mainnet.base.org/. We're working on implementing a fix.

3. monitoring Mar 24, 2026, 03:16 PM UTC

   A fix has been implemented and we are monitoring the results.

4. resolved Apr 01, 2026, 01:41 PM UTC

   This incident has been resolved.

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Started Mar 09, 2026, 08:29 PM UTC· resolved Mar 09, 2026, 09:54 PM UTC

1. investigating Mar 09, 2026, 08:29 PM UTC

   Users connecting to the Flashblocks websocket (mainnet.flashblocks.base.org) may have trouble connecting and receiving flashblocks. Block production is unaffected. We are currently investigation the issue.

2. monitoring Mar 09, 2026, 09:16 PM UTC

   We are monitoring a fix that has been implemented.

3. resolved Mar 09, 2026, 09:54 PM UTC

   This incident has been resolved.

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Started Feb 18, 2026, 05:31 AM UTC· resolved Feb 18, 2026, 04:56 PM UTC

1. investigating Feb 18, 2026, 05:31 AM UTC

   We are currently investigating the issue, blocks are being produced, but with no transaction included.

2. monitoring Feb 18, 2026, 07:16 AM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved Mar 10, 2026, 04:56 PM UTC

   This incident has been resolved.

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Started Jan 31, 2026, 10:42 PM UTC· resolved Mar 24, 2026, 01:13 PM UTC

1. monitoring Jan 31, 2026, 10:42 PM UTC

   We are actively monitoring network conditions. During periods of high congestion, users may experience intermittent transaction delays or transactions dropped. Submitted transactions can occasionally take up to two minutes to be included in a block or may need to be resubmitted. We are working on longer-term fixes to ameliorate this behavior and will share our plans and updates as we make progress.

2. monitoring Feb 05, 2026, 03:22 PM UTC

   We are experiencing heavy transaction volume resulting in inclusion delays. Active fixes are in progress

3. identified Feb 06, 2026, 01:46 AM UTC

   Update 2/6 01:30 UTC Overview We are actively scaling to meet elevated demand. While immediate infrastructure updates are underway to improve current throughput, we have also initiated several longer-term projects to ensure future stability and network performance. What we did today We’re landing changes to improve the RPC latency for eth_sendRawTransaction calls during load, and improve the efficiency of getting transactions to the block builder for selection: * [Live on Mainnet] - Doubled the disk IO throughput of our txpool * [Live on Mainnet] - Changed our `eth_sendRawTransaction` rate limiting window to smooth out incoming spikes. We will continue changing the rate limiting configuration in the coming days * Built and tested a more stable routing algorithm for sending transactions to the most efficient backend. We expect this to be on Mainnet within a couple of days What’s up next This work is expected to take 4 to 6 weeks. We anticipate this work to achieve stable transaction inclusion and block production * Implementing a transaction propagation redesign that removes the overhead of P2P when getting transactions to the block builder. * Optimizing and scaling configurations for `pending` and `queued` storage of transactions * Unifying the components of our block building, sequencing, and flashblocks streaming We will share updates here as we make progress.

4. monitoring Feb 06, 2026, 11:48 PM UTC

   We continue to see improved network stability after updating several elements of our routing infrastructure and as overall market volatility has subsided. We will continue monitoring network health and transaction success rate, while working on further upgrades to routing and transaction propagation layers which we described below. Several larger upgrades are deployed on devnets and testnets to ensure their stability under different network conditions, with plans to promote them to mainnet after we validate their safety. This remains our top priority and we'll continue to post updates with our ongoing progress.

5. monitoring Mar 24, 2026, 01:12 PM UTC

   Stability of block production and transaction inclusion are back to acceptable levels. We have deployed and confirmed reliability of several improvements to our block builder and transaction processing infrastructure, please reach out in discord with any issues.

6. resolved Mar 24, 2026, 01:13 PM UTC

   Stability of block production and transaction inclusion are back to acceptable levels. We have deployed and confirmed reliability of several improvements to our block builder and transaction processing infrastructure, please reach out in discord with any issues.

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Started Jan 22, 2026, 10:19 PM UTC· resolved Jan 31, 2026, 09:51 PM UTC

1. investigating Jan 22, 2026, 10:19 PM UTC

   Base is experiencing intermittent transaction delays due to network congestion. Submitted transactions can occasionally take up to two minutes to be included in a block. We are actively working on a fix and expect this behavior to continue until it can be tested and deployed.

2. monitoring Jan 30, 2026, 11:05 PM UTC

   We have identified an issue causing occasional dropped transactions during high-traffic periods. We have implemented a fix and are now monitoring the results. Update 1/31: The fix is still being tested. We still have high rates of transaction distribution failures and continue to investigate solutions.

3. identified Jan 31, 2026, 08:35 PM UTC

   We are now seeing high failure rates in transaction processing by the txpool and block builder. Users will experience high rates of transaction drops from the txpool, as well as overall high transaction inclusion times. We are actively troubleshooting this problem.

4. monitoring Jan 31, 2026, 08:47 PM UTC

   We have deployed a fix for the problem causing transactions to not propagate correctly to the block builder under load. Transaction inclusion has improved; we're continuing to monitor the fix in order to ensure the problem is resolved.

5. resolved Jan 31, 2026, 09:51 PM UTC

   We have validated the fix restored overall network stability. We will be conducting a full RCA and share a public postmortem in the coming days. Periods of increased network congestion can still occasionally result in transactions being delayed or dropped - we are working on longer-term fixes to ameliorate this behavior and will share our plans and updates as we make progress.

6. postmortem Feb 03, 2026, 11:21 PM UTC

   ## Postmortem: Transaction Drops and Inclusion Delays ## Summary On Saturday, January 31, 2026 between 19:17 and 20:41 UTC \(2 hours and 26 minutes\), Base Mainnet experienced a period of high transaction inclusion latency and increased mempool evictions. During this time, an estimated 20% of transactions submitted landed onchain. ## User Impact * **Dropped Transactions**: A total of 2.1 million transactions were dropped from the transaction pool and required resubmission by users. 512k transactions were included in blocks during the incident. * **Block Delays**: Spikes in incoming transactions, caused by the degraded inclusion times, resulted in block production delays. Approximately 2% of blocks in the incident window took longer than 2 seconds to build. ## Root Cause The root cause was a configuration change to how transactions were propagated between our mempool nodes and the block builder. The change was intended to address an ongoing \(but less severe\) incident causing periodic delays in transaction inclusion. The change increased the size of the queue for transactions waiting to be fetched from mempool nodes by the block builder. We determined that queue sizing was causing the builder to drop transactions that could have been executed during high-activity periods, resulting in the periodic delays. This had unintended effects as it intersected with unexpected behavior in the mempool clients that prevented proper management of mempool broadcasting queues. With the increased fetch size, a higher number of older transactions were attempted to be fetched which weren’t actually executable due to rapidly rising base fees. This led to failures in the fetch request and the builder retrying those requests, which triggered a negative feedback loop of the mempool nodes re-inserting them to the top of the queue. The builder continuously requested older transactions instead of the latest seen ones which were more likely to be executable. When organic network traffic spiked on Saturday \(peak tx submission rate was 25,000 TPS\), this cascaded into an inability for the builder to source executable transactions from the mempool nodes reliably. ## Mitigation Mitigation of the incident was rolling back this config change to restore the previous state of transaction propagation parameters. ## Our Learnings and Next Steps We are taking immediate and long-term actions to prevent this type of incident from recurring and to improve our response. ### 1. Technical Improvements We are improving the stability by optimizing the pipeline of getting transactions from ingress to the mempool nodes to the builder, while removing the unnecessary overhead of P2P gossip. Additionally, we’re actively working to scale and tune mempool to better respond to spikes in transaction volume. This project is in progress, and estimated to take approximately one month, with stabilizing milestones along the way. ### 2. Alerting and change monitoring We are focused on closing technical gaps related to monitoring: * **Alert Tuning:** We have updated our dashboards and alerts to better capture inconsistent degradation, like this incident, to ensure our team is immediately notified * **Change Monitoring**: We will establish active, temporary monitoring for major changes to mainnet infrastructure to catch even slight behavior differences during rollouts ‌ We encourage all partner teams to subscribe to the [Base Status Page](https://status.base.org) to remain in the loop. Additional information is shared on X \([buildonbase](https://x.com/buildonbase)\), and [Discord](https://discord.com/invite/buildonbase?utm_source=dotorg&utm_medium=nav).

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Started Jan 20, 2026, 02:30 PM UTC· resolved Jan 20, 2026, 03:10 PM UTC

1. resolved Jan 20, 2026, 03:51 PM UTC

   Base mainnet is experiencing periodically delayed blocks due to volatile activity. We're actively monitoring and working to improve the consistency of block building performance. Between 14:45 and 15:10 UTC on 1/20/2026, users may have noticed delayed transaction inclusion and degraded block building performance .

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Started Nov 06, 2025, 09:58 PM UTC· resolved Nov 12, 2025, 05:29 AM UTC

1. identified Nov 06, 2025, 09:58 PM UTC

   We are aware of degraded Flashblocks building, resulting in fewer broadcasted Flashblocks than expected. Users may also experience periodic reorgs of Flashblocks.

2. resolved Nov 12, 2025, 05:29 AM UTC

   Flashblocks building performance has has returned to expected values.

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Started Nov 04, 2025, 03:32 PM UTC· resolved Nov 17, 2025, 03:34 PM UTC

1. investigating Nov 04, 2025, 03:32 PM UTC

   We are currently investigating degraded connection stability to the Base Mainnet WebSocket endpoint for Flashblocks `wss://mainnet.flashblocks.base.org/ws`. Applications and nodes may experience intermittent connection drops to that endpoint.

2. identified Nov 12, 2025, 05:38 AM UTC

   We have identified bottlenecks with the Websocket endpoints distributing Flashblocks. Between Nov 5-10, several changes were made that reduced connection drops by 50%. However, investigation continues in order to further reduce connection instability and lower the latency in receiving messages. Updates will be posted here as progress is made.

3. resolved Nov 17, 2025, 03:34 PM UTC

   We have made improvements to the handling of rate limits in order to provide a more stable endpoint for Flashblocks.

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Started Oct 29, 2025, 11:36 PM UTC· resolved Oct 29, 2025, 11:57 PM UTC

1. identified Oct 29, 2025, 11:36 PM UTC

   A bug is causing inaccurate data to be returned from `eth_call` requests when used on Flashblock RPCs. This happens only when the ‘pending’ tag is used for `eth_call`. We’re working on a base/node release to fix this as soon as possible.

2. monitoring Oct 29, 2025, 11:53 PM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved Oct 29, 2025, 11:57 PM UTC

   This incident has been resolved.

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Started Oct 20, 2025, 06:58 PM UTC· resolved Oct 20, 2025, 09:07 PM UTC

1. identified Oct 20, 2025, 06:58 PM UTC

   Base Mainnet is experiencing high RPC and transaction inclusion latencies, as well as periodic inconsistencies in block production times.

2. resolved Oct 20, 2025, 09:07 PM UTC

   Block building and RPC performance has returned to normal

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Started Oct 20, 2025, 08:23 AM UTC· resolved Oct 20, 2025, 09:50 AM UTC

1. investigating Oct 20, 2025, 08:23 AM UTC

   We are investigating a reduction in Base network capacity.

2. identified Oct 20, 2025, 08:39 AM UTC

   AWS is having a major outage that is affecting Base infrastructure.

3. resolved Oct 20, 2025, 09:50 AM UTC

   The AWS outage has resolved. Batch submission has resumed, and transaction capacity has returned to normal.

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Started Oct 17, 2025, 07:27 PM UTC· resolved Oct 18, 2025, 03:34 AM UTC

1. investigating Oct 17, 2025, 07:27 PM UTC

   Periodic congestion on Base is causing delays in transaction inclusion.

2. resolved Oct 18, 2025, 03:34 AM UTC

   The mempool size has been increased to allow more transactions to be included in blocks quickly during periods of congestion. We will continue to monitor the network for delayed transaction inclusion.

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