This notification pertains to a consensus dilemma that transpired on the Frontier network at block 116,522, mined on 2015-08-20 at 14:59:16+02:00 – The problem has been resolved, please refer to “Fix” below.
Impact: Severe
Description of the issue: Consensus problem in the state database in geth related to the deletion of account data, which may occur during SUICIDE operations.
Impacted implementations: All geth builds up to and including versions 1.0.1, 1.1.0 and develop (“unstable 1.1.0”) were impacted. Eth (C++) and pyethereum (Python) remain unaffected.
Impact on expected chain reorganisation depth: Extended confirmation delay for eventual block approvals to 12 hours
Suggested temporary solution: Miners should switch to eth or pyethereum as soon as possible
Corrective measures implemented by Ethereum: Provision of fixes as detailed below.
Fix: It should be noted that the consensus issue occurred just prior to the announcement of the new release 1.1.0. When upgrading, ensure you update to the version you intended, as it may not be ideal to fix and upgrade from 1.0.1 to 1.1.0 (which has not been officially released yet) simultaneously. Fixes provided below are for version 1.0.2 – builds are available for v 1.0.2.
- Release 1.0.2 containing source and binaries can be located here
- If building from source: git pull followed by make geth – kindly utilize the master branch commit a0303ff4bdc17fba10baea4ce9ff250e5923efa2
- If using the PPA: sudo apt-get update then sudo apt-get upgrade
- We continue to pursue the brew patch
The appropriate version for this upgrade on Ubuntu AND OSX is Geth/v1.0.2-a0303f
Please be aware that you are likely to see the following message notification which will self-resolve after some time once your peers have updated their clients:
I0820 19:00:53.368852 4539 chain_manager.go:776] Bad block #116522 (05bef30ef572270f654746da22639a7a0c97dd97a7050b9e252391996aaeb689)
I0820 19:00:53.368891 4539 chain_manager.go:777] Detected known bad hash in chain 05bef30ef572270f654746da22639a7a0c97dd97a7050b9e
Updates:
- 20/08/15 17:47+02:00 The issue has been recognized, and a fix for geth is in progress. Geth(Go)-Miners should upgrade as soon as the fixes are released, and in the meantime, switch to Eth (C++) or Python, which remain unaffected.
- 20/08/15 19:38+02:00 Official fixes have been released; please see above.
- 20/08/15 21:19+02:00 Keep in mind that the consensus dilemma occurred just before the announcement of the new release 1.0.2. Thus, please ensure you obtain the desired fix, namely stay on 1.0.1 or upgrade to 1.0.2. Refer to “Fix” for further information.
- 21/08/15 11:30+2:00 Since the emergence of the consensus issue, we have been closely overseeing the chain and network. Based on network statistics, the majority of miners have upgraded to the patched 1.0.2 or shifted to eth. Our anticipation regarding the maximum probable chain-reorganization depth is 750 blocks.
