Setexcessiveblock

setexcessiveblock blockSize

Set the excessive block size. Excessive blocks will not be used in the active chain or relayed. This discourages the propagation of blocks that you consider excessively large.
Arguments:
1. blockSize    (numeric, required) Excessive block size in bytes.  Must be greater than 1000000.

Result:
  blockSize (integer) excessive block size in bytes

Examples:
> bitcoin-cli setexcessiveblock 25000000
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "setexcessiveblock", "params": [25000000] }' -H 'content-type: text/plain;' http://127.0.0.1:8332/