user62368: I'm running a private regtest network on GCP. I generated a list of 2000 vanity testnet addresses ordered sequentially from prefixes mooo1 to n2ooo with their respective pub/priv key pairs, and to prevent complications, I want to only have one private key for each node (change in outgoing transactions are sent to the original address). Because there's no security concern in my setting (it's just a performance test, no money or attacker is involved), I want to make each bitcoind instance only use a single private key for all transactions, and not generate new addresses through an HD wallet. This is because viewing transactions is much more streamlined. I can tell which node is sending bitcoins to which other node, and diagnose issues more easily. Is there an option in bitcoind to only use a single private key?

user51948: As of Bitcoin Core v18 and later, it is possible to create a blank wallet with no keys in it. You can then import the single key you wish to use. It can be imported as a descriptor (with importdescriptors), via the importprivkey RPC, or via the importmulti RPC.

62368: <p>I'm running a private regtest network on GCP. I generated a list of 2000 vanity testnet addresses ordered sequentially from prefixes <code>mooo1</code> to <code>n2ooo</code> with their respective pub/priv key pairs, and to prevent complications, I want to only have one private key for each node (change in outgoing transactions are sent to the original address). Because there's no security concern in my setting (it's just a performance test, no money or attacker is involved), I want to make each bitcoind instance only use a single private key for all transactions, and not generate new addresses through an HD wallet. This is because viewing transactions is much more streamlined. I can tell which node is sending bitcoins to which other node, and diagnose issues more easily. Is there an option in bitcoind to only use a single private key?</p>
 51948: <p>As of Bitcoin Core v18 and later, it is possible to create a blank wallet with no keys in it. You can then import the single key you wish to use. It can be imported as a descriptor (with <code>importdescriptors</code>), via the <code>importprivkey</code> RPC, or via the <code>importmulti</code> RPC.</p>
