With a small fraction of miners and a good chunk of nodes, a fork of the Ethereum chain is likely to be running.
Bitcoin block explorer Etherscan.io reports a drop in Ethereum’s node count in the last two weeks from more than 10,000 to less than 3,00 in the last two weeks. Despite the fact that chain explorers can only give preliminary estimations, this drop does coincide with the issue in node software that caused the chain to split barely two weeks ago. But why haven’t these nodes been recovered yet?
A glitch in a prior version of the most widely used Ethereum node software, Geth, led Ethereum’s blockchain to split into two chains two weeks ago. This meant that more than half of the nodes had hard split from the main chain, producing their own chain as a result of the hard fork.
A blockchain’s decentralisation relies on nodes, which are similar to miners. They act like accountants by comparing their own and other nodes’ transaction histories to ensure that the new transactions tally up correctly, much like accountants do. In addition, a larger number of nodes makes a blockchain stronger and safer.
Thank goodness for modern software, which allowed most miners to continue propagating genuine transactions on the main chain. So, Ethereum’s blockchain was still secure, but it appears that about 6,500 nodes are still running the old software and are stuck on a different chain.
6.500 nodes are absent from the forked-off network, but they can’t be seen for the time being, at least until someone creates a blockchain explorer for this new chain, allowing us to see what’s going on.
To compete with other cryptocurrencies, Ethereum’s node count has been lowered. We don’t know yet why or how Ethereum hasn’t been able to reclaim its nodes. It’s alarming that so many nodes continue to run on this branch instead of ensuring they’re up-to-date and on the main chain.
A few miners may have continued minting blocks as usual in the new fork notwithstanding the fork. Nodes could have been left unnoticed for this reason. Once these transactions have been made, it’s entirely feasible for them to opt out of reversing them.
How this issue will be rectified is still unclear. Every node and miner on this branch should upgrade their software to be interoperable with the main chain, which would be a simple solution. However, if they are hesitant to do so, a permanent Ethereum fork might be produced.