F2Pool enables "Classic" mining on Core 0.12.0 software

[arnoudk]

In a rather unexpected turn of events....

F2Pool supposedly signed a document claiming that they would only run "Core compatible" consensus code:

We will only run Bitcoin Core-compatible consensus systems, eventually containing both SegWit and the hard-fork, in production, for the foreseeable future.

[source]

Well, "Bitcoin Core-compatible consensus systems" is interpreted by F2Pool to include the following gem:

We are testing Classic mining on stratum.f2xtpool.com at port 3333. F2XTPool is currently powered by Bitcoin Core v0.12.0, with -mempoolreplacement=false, only block version is set to 0x30000000. We are not going to run Classic node in production, for the “foreseeable ”future.

And what about this one!

[–]macbook-air 16 points 2 hours ago

• We have agreed in Hong Kong that we are not going to run Classic in production, for the “foreseeable” future.
• Classic is compatible with Bitcoin Core unless 75% target is met, which is not “foreseeable”.

So, they are "honoring" their agreement, in their own way I guess, by running a Core node configured as Classic.

[kingscrown]

This is great news man!

[iFixBTCmemoryIssues]

Hats off to F2Pool, well done gentlemen

[throughnothing]

This is very confusing, I'm not sure exactly how to interpret this. It sounds like they are running Bitcoin Core (NOT classic), but just setting the version number to make it LOOK like it is classic. That seems like a bad thing to me, but this all seems unclear and confusing.

[arnoudk]

This is very confusing, I'm not sure exactly how to interpret this. It sounds like they are running Bitcoin Core (NOT classic), but just setting the version number to make it LOOK like it is classic. That seems like a bad thing to me, but this all seems unclear and confusing.

Yes this is exactly what they are doing.

As long as 75% of the last 1000 blocks are not marked Classic, nothing will change. When that mark is hit, they will have to upgrade their nodes to Classic (or Core will most likely be pressured to create a version with the 2 MB block patch which they can just copy from Classic).

If Core does not make such a change, they will have to upgrade to Classic - or make the changes themselves to Core.

There is a 4 week period for them to make the switch. This is more than enough. I know miners have a more complicated setup, but it took me all of 5 minutes to switch to Classic. For them, it would be no different than upgrading a version of Core.

Never a dull day in Bitcoin-land.

[throughnothing]

I see, thats a very good point. Thanks for explaining. The reason I was (am?) suspicious, is because we've seen this before where miner's mine different version blocks without actually running that software version. Then when the 'trigger' happens, they don't actually switch, they've essentially just been lying. Hopefully when/if the Classic trigger happens, those guys will stay honest and actually upgrade in the 28 day window.

[arnoudk]

I see, thats a very good point. Thanks for explaining. The reason I was (am?) suspicious, is because we've seen this before where miner's mine different version blocks without actually running that software version. Then when the 'trigger' happens, they don't actually switch, they've essentially just been lying. Hopefully when/if the Classic trigger happens, those guys will stay honest and actually upgrade in the 28 day window.

Me too. If they don't, it is an attack on the network. Not a smart move for a company with many millions invested that would be worthless or worth less if they perform a successful attack.

However, there are more ways to do this kind of thing. They could run Classic, wait until the trigger, and then uninstall Classic and run Core. In effect, this is the exact same type of attack.

You'd expect miners to be somewhat rational and not destroy their business.

I believe that what we are seeing is fear. Miners want to scale, but they want Core to do this. Core won't, at least not for a long time.

I truly believe that miners who want core to scale should act as follows:
Run classic. Mine >75% out of the last 1000 blocks.
Wait for the trigger.
Demand that Core makes the change needed, or run Classic.

Core will make the change. They work for Blockstream, and did they not just get a 75 million dollar investment? What will the investors say if the people in the company they invested in just stop showing up for work? They WILL continue to work, Core will continue to be a platform that miners will continue to run.