F2Pool, a Chinese mining pool also referred to as Discus Fish, which holds the largest share of the Bitcoin network’s hashrate at 26%, has been experiencing a series of extreme DDoS attacks.

The attacks began to target the F2Pool Bitcoin mining pool almost immediately after the F2Pool team announced their decision to “test” Bitcoin Classic by launching a subpool in which miners can mine Bitcoin Classic blocks.

Peter Todd and other Bitcoin experts requested the hackers and the individuals behind the series of DDoS attacks to terminate them immediately, as they are delaying the mining pools and companies to reach a consensus on the block size debate.

Whomever is DoS attacking f2pool please stop. You're only making it harder to come to consensus.https://t.co/GoicJNhcMY — Peter Todd (@petertoddbtc) February 25, 2016

Behind the DDoS attack

Some bitcoin enthusiasts and supporters of Bitcoin Classic claim that the attacks have been directed and paid for by Bitcoin Core supporters, and its developers, to forcefully cause Bitcoin Classic nodes to become inoperable.

A hacker, or a hacking group, that goes by the online alias botneko-chan stated on a forum that they have been paid to launch professional DDoS attacks on F2Pool’s Bitcoin Classic subpools.

"Just paid, I'm professional ddoser lol. Don't know why someone want to bring it down. Maybe increasing block size will decrease miners profit? I'm using bitcoin a lot but don't care about it's politics too much, XT had too fast block size grow rate which looks unrealistic to me. I think BIP100 is okay since it allows voting and also bitcoin unlimited also seems like good idea and looks simpler for me. If classic will fork to 2mb blocksize and it would be not enough then what? Next hard fork? I think protocol should support miner voting by design,” the hacker himself said on Reddit.

Jonathan Toomim, the leading developer and founder of Bitcoin Classic, further explained that Chinese miners and mining pools are quite skeptical towards Bitcoin Classic as they prefer not to change pool information on their hardware to adopt the 2 megabyte hard fork.

“Actual miners are lazy,” said Toomim. “They don't like to change pool information on their hardware very often, because that would require logging into each of your machines and copy-pasting in new data to a web form and clicking submit. A typical mining farm will have hundreds to tens of thousands of these machines. The approach that Slush is taking is different. Rather than requiring users to reconfigure each machine, Slush is giving users a way to switch all of their hardware between Classic and Core by clicking on one button on Slush's website. This should result in much faster changes.”

As of now, leading bitcoin mining pools, including Antpool, F2Pool and BitFury, are supporting the roadmap and development of the Bitcoin Core development team.