[FRAC] Fractalcoin detailed post fork update

[Fractalcoin]

Detailed post fork update

As some of you may be aware Fractalcoin experienced some minor difficulties when transitioning to the new fork. This was due to a flaw in the fork checking code in that it only considers raw block height, as such it did not attempt to determine if the new fork was actually valid. We mitigated these issues promptly and disabled the problematic code for pools. There will be no mandatory wallet update required regarding this issue, we will however be fixing the problematic code as a precaution for the future and releasing an optional wallet update. The network has progressed enough that this issue is no longer anything to worry about.

During this period the Fractalcoin network never became unsafe, there was no creation of alternate forks and also no risk of a double spend.

Overview

Initially the fork was a success with 70% of network hashrate present on the new fork as planned. The issue occurred when the fork checking code saw both the new and old forks on the network after around 14 blocks, causing safemode to be enabled. This happened due to a flaw in the fork checking code in that it only considers raw block height, making it unable to effectively ensure that a fork is valid.

In planning for this fork we had altered the block reward for a set number of blocks, this should have ensured that the old fork would not conflict with the new fork but the flaw in the fork checking code overrode these efforts.

With safemode enabled, RPC calls used by mining pools were disabled, this caused mining on the new fork to pause temporarily. Upon seeing these issues we promptly added a checkpoint block in an effort to restart mining but shortly after this safemode re-triggered. The final solution that we decided on was disabling the problematic fork checking code entirely for pools until we can replace it with fully functional code.

We will be analysing this code over the coming days and writing a substitute to ensure that this is corrected. We have also submitted this issue to the Dogecoin devs along with our findings and recommendations.

All services should now be back online and the network is running as intended. This was an isolated incident and as such should cause no further problems.

We would like to thank you all for your continued support of Fractalcoin.