-chain

bitcoind

-chain=<chain>
      Use the chain <chain> (default: main). Allowed values: main, test, signet, regtest

bitcoind, .bitcoin/, bitcoin.conf, Dockerfile, Bitcoind ports( 8332 18332 18443 8333 18333 18444 ), -chain, -datadir, -server, --help, Bitcoind logs, Bitcoind changelog