The Great Firewall of China, used by its government to regulate access to foreign internet sites, has blocked Etherscan, one of the most popular sources of ethereum blockchain data.
A block explorer is a website or a tool that make it easier for end cryptocurrency users to track blocks, wallet addresses, network hashrate, transaction data and other key data on a certain blockchain, like the Bitcoin (BTC) blockchain or the Ethereum blockchain. For Bitcoin, there are a number of block explorers, including Blockchain.com or Blockexplorer.com. The actual blockchain transactions are not stored in any centralised database.
As of Tuesday, Etherscan, an ethereum block explorers, was inaccessible from IP addresses originating from mainland China. Etherscan has joined a list of sites such as Google, Facebook, Twitter, and Reddit at the foot of the firewall.
Internet users had been sharing on WeChat the hash of those transactions using etherscan.io, which even prompted WeChat to later block users from viewing the exact etherscan.io URLs from inside the messaging app.
At the meantime, other ethereum explorers are still accessible from inside mainland China.