The submitblock RPC accepts a block, verifies it is a valid addition to the block chain, and broadcasts it to the network. Extra parameters are ignored by Bitcoin Core but may be used by mining pools or other programs.
submitblock "hexdata" ( "dummy" )
*bitcoin-cli help submitblock
submitblock "hexdata" ( "dummy" ) Attempts to submit new block to network. See https://en.bitcoin.it/wiki/BIP_0022 for full specification. Arguments 1. "hexdata" (string, required) the hex-encoded block data to submit 2. "dummy" (optional) dummy value, for compatibility with BIP22. This value is ignored. Result: Examples: > bitcoin-cli submitblock "mydata" > curl --user myusername --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "submitblock", "params": ["mydata"] }' -H 'content-type: text/plain;' http://127.0.0.1:8332/