Genesis mismatch bug

[krisbitney]

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• This is not a support question.

Description of bug

Hi,

I tried asking my question as a support question on the polkadot stackexchange, but I think the issue may be a bug rather than a mistake I am making.

See: https://substrate.stackexchange.com/questions/12187/how-to-overcome-genesis-mismatch

My team and I launched a testnet network built on Substrate. When we launched the testnet, we weren't aware of how chainspecs worked. We didn't realize syncing from the Rust chainspec would break as soon as we pushed an over-the-air runtime upgrade.

New nodes get a "genesis mismatched" error and are unable to sync with the network. I have tried obtaining a chain spec by calling substrate.rpc.syncstate.genSyncSpec on a node that is connected to the network, but the retrieved chain spec does not work. I am under the impression that the retrieved chain spec should work, hence the reason I think this is a bug.

Is this a bug, or is this expected behavior?

This is a huge problem for us. There is no other chain spec JSON file. This is a new network that has received a few patch updates. We don't want to totally reset the testnet. In order to get people to use the testnet and provide feedback, we already incentivized participation with the promise of a future airdrop. Resetting the testnet would reset the records of everyone's usage and upset our community. So we are pretty stuck.

Example of the error:

Report 12D3KooWSLXobU5fj93hM9oY956obg6cV8pYJ4tMdJ4EoekwceWm: -2147483648 to -2147483648. Reason: Genesis mismatch. Banned, disconnecting.

Please consider looking into this. Thank you.

Steps to reproduce

No response

[bkchr]

Not really a bug.

Go back to the exact node version that you used to launch the network. Run your_node build-spec --raw --chain THE_NAME_YOU_USED_TO_LAUNCH_YOUR_CHAIN > chainspec.json.

Then take some other node and run it with your_node --chain PATH/chainspec.json.

[krisbitney]

Thank you. You are completely right. I was able to generate a working chain spec using your advice. I am embarrassed to admit how much time I spent researching and experimenting before posting here and getting such a quick response from you. I appreciate your help more than you know! @bkchr