invalidateblock "hash"
Permanently marks a block as invalid, as if it violated a consensus rule.
Arguments:
1. hash (string, required) the hash of the block to mark as invalid
Result:
Examples:
> bitcoin-cli invalidateblock "blockhash"
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "invalidateblock", "params": ["blockhash"] }' -H 'content-type: text/plain;' http://127.0.0.1:8332/