Shortly after the Berlin hard fork, Etherscan and OpenEthereum are stuck on one block.
On Thursday afternoon UTC, the OpenEthereum client for Ethereum, formerly known as the Parity client, is reportedly down for a number of users, including the common block explorer Etherscan.
The OpenEthereum client has been stuck on block 12,244,294, or only 294 blocks after the Berlin hard fork, according to numerous user comments on GitHub. The error message appears to mean that the client is refusing the new blocks because its Merkle root state is incorrect.
The problem appears to be limited to OpenEthereum nodes, with Geth appearing to be unaffected. Etherscan, the famous block explorer, was down due to issues with the OpenEthereum client. Even though other explorers are updating correctly, its homepage displays block 12,244,294 as the last block to be mined.
The cause of the problem is still unknown, and the team is currently working to diagnose and resolve the issue. Etherscan will remain unusable before that happens.
The Ethereum blockchain and several service providers, such as Infura, are unaffected by the problem since it only affects OpenEthereum. There is no alternate chain with its own transactions this time, unlike the previous consensus bug. Given the timing of the Berlin hard fork, some of its modifications are likely to have been applied incorrectly.