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geth — datadir <path to your testnet directory> — networkid 12345 — rpc — rpcaddr “localhost” — rpcport 8545 — rpccorsdomain “*” — rpcapi “eth,net,web3,personal,admin,mine” — mine — minerthreads 1 — nodiscover — maxpeers 0 miner
chmod 400 "/path/to/your/file.pem"