Ethereum blockchain accidentally forked

Rage Comment : The slight differences in the way Ethereum's two clients, Parity and Geth, process transactions have led to the emergence of two chains at the same time, affecting the normal progress of transactions. This is exactly the same as the accidental incident of Bitcoin a few years ago. For this reason, Parity and Geth are already discussing solutions, and transactions may be rolled back. However, it is best to stop trading before the system is repaired.

Translation: Annie_Xu

At 3pm London time on the 24th of this month, two major Ethereum clients, Parity and Geth, suddenly became out of sync, unexpectedly causing two chains to run in parallel. Users, especially exchanges, had to terminate transactions or wait for multiple audits and confirmations until the problem was resolved. Developers immediately took emergency measures and discussed solutions together.

Geth developer Nick Johnson said:

"The root cause is an extreme case of state clearing. If an empty account has been 'touched', it will generally be deleted. However, when the instruction lacks 'gasoline' (the currency required to pay for the number of code steps in blockchain transactions), Geth still deleted it, while Parity did not delete it."

EIP (Ethereum Improvement Proposals) does not clearly indicate which approach is correct; it is just that everyone agrees that Parity is more reasonable. It can only be said that the lack of standards and consensus testing is an unfortunate mistake.

The current solution for Geth is to use a patch to synchronize it with Parity. It is expected that the solution will be completed soon.

Gavin Wood

Gavin Wood, founder of Parity Technologies, said that Geth has a vulnerability, which means that "half of the mining network uses imperfect Geth, and the other half uses perfect Parity. Parity will continue to be unchanged", but transactions using Geth may need to be rolled back.

Johnson said:

"Geth's fork will be seen as unconventional and will be abandoned. Most transactions will be saved on the fork, so most users don't have to worry about rollbacks. The main problem is that when interacting with other systems, there may be problems with transaction finality, such as whether the exchange will recognize the deposit and convert it into fiat currency."

Wood said that Geth will be fixed and the "main chain will continue to operate normally", but he advised everyone to be cautious because the operating environment of the Ethereum blockchain has changed.

This situation is similar to the Bitcoin forks in 2013 and 2015. Both were caused by system upgrade bugs that accidentally led to the emergence of two chains. Mining was then carried out on both chains, and finally all transactions were rolled back to one chain, and the other was abandoned.

Ethereum was also caused by an upgrade. Two days ago, in order to fix some vulnerabilities, Ethereum was optimized; however, the difference in the operations of the two clients still caused the network to fork.

Therefore, users using the Geth client are advised to wait for a solution to come out before continuing transactions.