Non-public Keys Relationship in HD Wallets

1. What is the relationship between the primary pkey/addr (the one with hdkeypath: m/0'/0'/0 and the third one m/0'/0'/2?

They’re derived from the identical mother or father key. Apart from that, there is no such thing as a relation.

Does the primary key/addr is the grasp (key) who can get well all later keys generated within the pockets.

No. They’re each baby keys of the important thing at m/0'/0'. The precise grasp personal key (the important thing at m) is just not exportable. There’s a HD seed (which is used to generate the grasp personal key at m), however that is solely exportable by means of the dumpwallet RPC.

2. I solely backup the personal key of m/0'/0'/2, and eliminated the entire pockets (the .dat file). Is there a danger of this methodology? Since I solely select to make use of this key/addr to obtain and retailer BTC.

Do not try this, you’ll lose cash. Whenever you ship Bitcoin, Bitcoin Core will generate new change addresses and ship any change there. These change addresses have totally different personal keys. With out them, you’ll lose cash.

Moreover, by reusing the identical handle, you’re considerably hurting your privateness. By utilizing the identical handle time and again, anybody you transact with will know the way a lot cash you may have in your pockets and be capable to see your whole incoming and outgoing transactions. This enables anybody to trace your spending habits.

3. I later create a brand new pockets and restore this m/0'/0'/2 key with command importprivkey. and ship some BTC to different individuals, and located it generate a CHANGE addr, so I additionally backup this new addr’s personal key too. Since I primarily use this m/0'/0'/2 to retailer long run BTC, and won’t use it to make quite a bit transactions. So I maintain the privatekey of m/0'/0'/2, and maintain backups priv keys of change addresses it generated, then drop all pockets recordsdata. Is that this methodology sufficient to revive all my balances in a futher day.

Bitcoin Core always generates new change addresses. The one time you overlook implies that you’ll lose cash. In the event you unintentionally request a brand new handle and use it, you’ll lose cash.

Usually, backing up particular person personal keys is just not really helpful. You need to again up your entire pockets.dat file itself. There is no such thing as a have to export every key individually and again it up in that method. That could be a surefire option to lose cash sooner or later sooner or later.

4. Can the personal key of m/0'/0'/2 be used to get well the change addresses’ personal keys? (What’s the grasp seed of HD pockets, it’s the personal key of m/0'/0'/0?)

No. The change addresses are unrelated. You would want to have the HD seed talked about beforehand with the intention to derive them.