Ethereum developers took significant measures to address the finality issues that occurred at Beacon Chain. The developers rolled out patches for Prysm Labs and Teku clients in response to two Beacon Chain finality issues in 24 hours. The Beacon Chain serves as the consensus layer for the Ethereum network.
The Beacon Chain introduced proof-of-stake to the Ethereum ecosystem. It was merged with the original Ethereum proof-of-work chain in September 2022. The Beacon Chain introduced the consensus logic and block gossip protocol which now secures Ethereum.
It is important to note that no exact cause of the issue is still known. Further, end users did not experience any transaction issues, the Ethereum Foundation highlighted the importance of client diversity in maintaining a robust network. The Ethereum Foundation is still investigating the full cause of the finality issues but has noted that they were likely caused by a high load on some consensus layer clients due to an exceptional scenario. Teku and Prysm have implemented optimizations to prevent future finality issues, ensuring a more stable network moving forward.
Prysmatic Labs co-founder Preston van Loon said that the issue on Thursday appeared to involve something that “happened to cause several client implementations to work hard to keep up with the chain. As the outage seemed to reappear on Friday, he tweeted that “we’ve tagged v4.0.4-rc.0 for prysm which has the fix, but we haven’t had time to test it thoroughly.”
This incident spurred many in the crypto community to take to social media to discuss and try to figure out what went wrong. Prominent venture capitalist and Ethereum supporter Adam Cochran tweeted out: “ETH beacon chain finality has now failed for over an hour, we’re at inactivity leak time and there is no denying this is now a liveness fault. Hoping that this is just an implementation issue for a single client to fix and not a larger protocol issue… either way, not good.”
An Ethereum consultant shared on Twitter that the Ethereum Foundation stated that achieving finality was not possible after 3 and 8 epochs. It seems that the problem was due to a heavy workload on certain Consensus Layers clients, which was caused by an unusual situation. Although the network failed to finish, both live and end users managed to continue their operations on the network because of the variety of clients, “since not all client implementations were impacted by this unusual situation.”
Ethereum’s beacon chain briefly lost finality twice in the week. The first occurrence caused the network to stop finalizing blocks for around 25 minutes and the second outage lasted for over an hour. The first time this happened on May 11 the Ethereum network appears to have suffered a technical issue that, for a temporary period, meant that transaction finality wasn’t occurring. Even at that time, the issue was not clear. Another happened on May 12 for an hour, during this block finalization was hindered.
Finality is the assurance or guarantee that cryptocurrency transactions cannot be altered, reversed, or cancelled after they are completed. The latency level of a blockchain will ultimately affect the chain’s finality rate. It is used to measure the amount of time one has to wait for a reasonable guarantee that crypto transactions executed on the blockchain will not be reversed or changed.