Ethereum's beacon chain suffers another finality issue

The Ethereum network appears to have suffered another technical snag that kept transaction finality from happening for about an hour on Friday. The issue drew fresh concerns about the stability of the network, as it came less then 24 hours after a similar event yesterday.

Like on Thursday, data sources for Ethereum network activity show that the issue was experienced by validators, which propose attestations as the network processes transactions. Ethereum epochs 200,750 thru 200,758 saw a significant reduction in the number of attestations received, according to Data provider Beaconcha.in.

"Ethereum’s Beacon Chain stopped finalizing transactions for roughly an hour," The Block research director Steven Zheng said. "It is currently unclear what the reason is behind the halts but some people think it was due to some bugs in staking clients or MEV infrastructures."

"While transactions did not stop on Ethereum they were not finalized which meant the chance of transactions being reverted were higher than if things worked as intended,” Zheng continued.

'Ethereum did not go down yesterday'

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 really 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."

"We have identified a few areas where Prysm could perform better in a scenario like we saw yesterday in Ethereum mainnet and we are preparing to release these improvements as fast as safely practical," he said on Friday, before the issue seemed to reappear. 

He pushed back against worry that the entire protocol had failed. 

"To clarify: Ethereum did not go down yesterday," he wrote on Twitter. "Blocks weren't even close to being full, despite limited block capacity. You could have transacted during the epochs struggling to finalize, there was plenty of block space when blocks were produced."