Ethereum's Hard Fork


The long-planned Ethereum fork is coming on Jan. 16th. With Constantinople going live within weeks.
Constantinople Activating in January
Constantinople is one of the key milestones in Ethereum’s roadmap to version 2.0, which moves the protocol from proof-of-work (PoW) to proof-of-stake (PoS). Compared to the larger plan, Constantinople’s changes are minor. The update introduces a few new opcodes—pieces of logic programmers use to develop smart contracts, delays the intensity of the mining “difficulty bomb” and reduces the reward for finding blocks, and alters and optimizes the way gas is consumed.

Once activated, nodes running Constantinople will be incompatible with the previous version of Ethereum, resulting in a “hard fork” of the blockchain. Ethereum team lead Péter Szilágyi predicts that the protocol will fork on Jan. 16th, when the blockchain reaches block 7,080,000.

Once the hard fork is activated, nodes running the latest software will operate on the new fork. Legacy nodes that continue operating on the original blockchain will no longer get compensated because the tokens on the old fork will likely become worthless. Users will automatically have their ether available to spend on the new fork.

This Could be good news, however only time will tell…


I am sorry, but i have to ask … we will need new software to mine ETH? or can i stick with 11.x? or should i move to 12.x now?


I hate to bring what might be bad news, but this fork will kill the last of @Anorak’s pools unless he comes back to do maintenance.

@HEki you should check the appropriate site for your software. (Or Google) You’re using Claymore? Check the Claymore thread on bitcointalk.

I know Claymore has committed to ProgPow support so I have no reason to believe he won’t do Constantinople in the meantime. I can’t find a statement to that effect yet.


Claymore has posted saying he will update the miner when it’s ready to go live.

(Yes I will update my miner to support ProgPow when ETH will be ready to switch to it.)
Taken from /

Seems to be mixed reaction as to how good or not Eth will be after the hard fork.


Thank you guys for the info!


gtdwh, can you provide some more explanation? When you state that “nodes running the latest software will operate on the new fork…” Does “node” mean the Ethereum wallet, the miner’s instance of Claymore (for example), the mining site or something else?


From what I understand, as an miner the majority of wallets should be ok, depending on which one you use
probably wise to check, the mining pool/site will update, A network upgrade is a change to the underlying Ethereum protocol, creating new rules to improve the system.
Miners may have to check which mining software is updated , like claymore, He has said he will update, if the pool does not update, You will be stuck on an incompatible chain following the old rules and you will be unable to send ether or operate on the post-upgrade Ethereum network.
Short version.


thanks, that is helpful.


It’s on hold for now,

The upcoming #Ethereum Constantinople Hard Fork will be postponed due to a recently identified security issue with one of the EIPs:


This is not unusual. He hasn’t upgraded his Ubiq pool either. They forked their chain to a new algo back in November and Anorak still hasn’t bothered to do any maintenance to upgrade it.


I might not say “bothered,” but it is true that @Anorak was unavailable for a couple of months and no maintenance was done over that time. Things are being fixed now, and there should be an update soon.