No Fork, No Fire: Segwit2x Nodes Stall Running Abandoned Bitcoin Code

The Segwit2x bitcoin fork may have been formally called off, but as many as 150 nodes still running its code have stopped accepting transaction blocks.

Data from Bitnodes shows that 95 nodes are currently running 2x software and are stuck at block number 494,782. CoinDance, another network data site, says that 154 nodes are running the "btc1" software as of press time.

The situation is a curious one, given that the 2x fork effort – advanced by a group of startups, miners and community supporters as a way to expand the transaction capacity of the bitcoin network – was effectively disbanded on Nov. 8 following an email circulated on the project's mailing list. Yet despite the abandonment, dozens of nodes continue to be operated that use the most-recent btc1 software release.

Today's stoppage appears to be driven by an issue in the code that prevented miners from actually producing a larger-than-1 MB block that would push nodes running Segwit2x into its own chain. Amid growing discussion in the project's Slack channel, developer Jeff Garzik released a patch aimed at easing the creation of a bigger transaction block (though in the absence of strong mining support, it's unlikely that the network will advance).

And even though the Segwit2x fork itself won't move forward, today's development revived some of the acrimony between those who supported the effort and those who have voiced vehement opposition to it.

One particular point of contention is the exact block number at which the fork was supposed to activate.

Past materials indicate that this block would have been 494,784, leading critics to say that developer Garzik had an "off-by-one" error and that, if carried out, the nodes planning to fork could have been caught in limbo. Garzik, in turn, has argued that the code is operating as intended in the absence of significant hashing power.

It also remains to be seen whether some – if any – of the nodes in question see their software changed. Data from Bitnodes suggests that a number of them reside on hosting services from companies like Amazon and Alibaba.

So unless that larger-than-1 MB block arrives, the nodes that are running the software will have to keep waiting.

Disclosure: CoinDesk is a subsidiary of Digital Currency Group, which helped organize the Segwit2x agreement.

Frozen clock image via Shutterstock