Hot answers tagged

12

By default, Bitcoin Core creates 100 addresses the first time it starts, and tries to keep 100 not-yet-used keys in wallet.dat 'keypool' (when you unlock the wallet to make a payment it will generate more). So you do not need to backup continuously. The 'getinfo' RPC command will tell you the time when the oldest not-yet-used key was generated ('...


11

This is how you obtain the private key for an Armory wallet: In Armory-Qt, click on Wallet Properties (or in the newer versions, double click on your wallet to open your Wallet Properties), then click Backup this wallet>See other backup options>Export Key Lists then click the button Export Key Lists. Enter your passphrase and Armory will show your wallet's ...


8

For Mycelium, the actual file that contains the encrypted keys are in the sqlite3 file. You can see in the source code that though there is in-memory storage, it's used mostly for testing and that the main way in which Mycelium data is stored is in a sqlite3 file. Sqlite, if you aren't familiar, is a very simple relational database that contains the whole ...


8

It is important to be able to recover your private keys using only tools you fully control. That protects you against failure of infrastructure you would otherwise need to transfer your funds. There are lots of stories of corrupted backups, unreadable backups, and backups that didn't actually include the private keys. Storing your private keys unencrypted ...


6

Yes. Yes. No. Note that that the software's encryption encrypts only the private keys, not transaction and address book information, so to protect your privacy you may want to add encrypting the file itself.


6

The Bitcoin-Qt/bitcoind client's keypool has by default 100 Bitcoin addresses. Each spend transaction that has change chews up one of those addresses. Additionally each click on New Address will consume an address from the keypool as well. So you should be able to get by without a new backup until after 100 spend transactions plus any requests for a New ...


6

Ben Kaufman answered this on Twitter. The main caveat in a multisig wallet is that, while you need only a threshold of devices (ie. 2 of 3, 3 of 5, etc.) to sign a transaction, losing access to even a single device could potentially prevent you from being able to spend the funds - if you don't back up properly! The reason is that (usually) in order to make a ...


5

Since wallet.dat is mostly a collection of private keys, you will simply lose all private keys that you have not duplicated or copied. It also by default stores the next 100 Bitcoin addresses it will give you when you generate a new address as a safety measure. Bottom line You will lose the copy of the private keys to addresses you've created or added but ...


5

You are correct. However, in all open source wallets that follow the proper Bitcoin Improvement Proposals (BIPs) people will be able to replicate the encryption logic so you can use your passphrase to get access to your private keys again. Still, I would recommend, for the majority of your bitcoins, to store them to a paper wallet with the private key ...


4

I'll go through your question clause by clause: I've made an offline address You're doing good. and only have the key stored on 2 encrypted flash drives stored in different locations As long as only you know the password and the password is sufficiently strong, this is probably secure. with the private key written physically on paper and stored ...


4

If you made more than 100 transactions and individual receiving addresses combined, yes. Best way to find out is to try.


4

Blockchain.info has two separate "mnemonics", one for each password (using that term loosely, since it's not the type of permanent mnemonic every other mnemonic-capable wallet uses). I agree they don't make it at all clear that you gain a second one once you add a second password. It sounds like you only have the main one. If you have completely forgotten ...


4

Restoring a wallet on a fresh machine: Start Bitcoin-Core (daemon or Qt), shut it down after it has started up (you only do that to create the necessary data directory) Replace wallet.dat with your backed-up wallet.dat (see https://en.bitcoin.it/wiki/Data_directory if you can't find the data dir) Startup Bitcoin-Core, wait until your node is in sync (can ...


4

Using words to back up wallets is a process described in BIP 39. Basically, the mnemonic is converted into a seed. This seed is then used as the seed to a Heirarchical Deterministic (HD) wallet, as laid out in BIP 32. The seed is used to generate a Master Extended Private Key, from which all other private keys can be generated. The child key generation ...


4

This method is used by Bitcoin Core (and few others) and comprises of backing up a wallet.dat file. It's a file that holds keys to spend outputs, addresses, transaction information, and other metadata such as contacts. It has a different location based on an operating system. Windows: %APPDATA%\Bitcoin Linux: ~/.bitcoin/ Mac OS X: ~/Library/...


3

1 Yes if you use that wallet only to keep coins but you don't use it to pay. 2 Same as answer nº 1 3 No. Trying to keep transactions difficult to trace, whenever you transfer bitcoins a second transaction is placed. That transaction moves a small amount to a new address created in your wallet. I don't remember how many "wallets" within your wallet are ...


3

(I suppose you have the Bitcoin-Qt client.) Taking a backup of the Bitcoin folder will do it. Copy the folder to an external hard drive of a different partition. Reinstall your system. Install Bitcoin-Qt again. Move the folder back. Note that to keep your bitcoins, only the wallet.dat file is required. But when you copy the whole folder, you will ...


3

TL;DR: If you have a frequent recurring backup you are safe, otherwise use a deterministic wallet. No, you are not safe in that scenario. Let me rephrase that, you are not safe if you really want to use your the coins from your addresses. Wallet.dat file stores all public and private keys of your current addresses but standard client generates a new ...


3

Bitcoin-Qt is a full p2p network client, so to work, it needs to sync with the network. Basically, it will download every transaction that was done with the currency (~15 GB in total at the moment). Might take one or two days, then you'll be good to go.


3

I've looked at Bitcoin's backupwallet code, and that error is triggered by a filesystem error. I can't tell what kind of filesystem error it is, though. Please open debug.log in the Bitcoin directory. There should be a line like <date + time> error copying wallet.dat to <path> - <kind of error> This is the most common type of error: ...


3

Yes, it is completely safe to exclude the blocks directory from your backup process. In the event that you lose all your files and need to restore from backup, Bitcoin will download all missing blocks. This may take some time, but there is no information in that directory that is unique to you.


3

Points for Hot Wallet Inheritability: Lower exposure to risks - use hot wallets that are BIP 39 compliant and share your 12 to 24 recovery passphrase and associated password in advance. Higher exposure to risk - share passwords on your devices that have hot wallets. BIP 32 compliant wallets make it easy to have the same logical wallet deployed on to ...


3

The best way to restore a backup file is always to use the same app used for creating the backup. In other words, install the app again, then use Options > Safety > Restore wallet.


3

Yes you will be able to access the same coins with both devices. You can think about it like if you make a copy of a key to your home, and give it to someone; both people will be able to open the same door.


3

Quoting https://en.bitcoin.it/wiki/Data_directory#Mac : Mac By default Bitcoin will put its data here: ~/Library/Application Support/Bitcoin/ You can access that folder by opening a new Finder window --> then by going to "Go" --> "Go to Folder..." (or pressing command + shift + G), and then pasting the above path into the window that ...


3

It is a common misconception that there are actual objects or chunks of data that are Bitcoin and that your wallet receives. That is actually not the case; your Bitcoin are just values attached to outputs created by previous transactions. Most of these outputs (and the type that your Ledger is designed for) require that the spending transaction contain a ...


3

Unlike bitcoin stored in an on-chain wallet, funds in the lightning network are stateful. Some channel data cannot be deterministically reconstructed like keys derived from a BIP32 seed. If you do not have backups and your channel counterparty is non-responsive, you will likely experience permanent loss of funds. Make sure to have backups of your channel ...


3

There are 3 approaches to backup/restore your Electrum wallet with Bitcoin, depending on whether you use Electrum to manage a HD or non-HD wallet, you may or may not have a 'seed'. If your wallet is a HD wallet, to restore/backup your wallet, simply use the 'seed' (12 words). If your wallet is not HD, to restore/backup your wallet, simply restore/backup ...


3

It depends on what kind of wallet you have. Traditionally each private key was generated randomly by your wallet software. In this case every private key needs to be backed up. Recently deterministic wallets have become popular. Deterministic wallets randomly generate a seed, and then use that seed to deterministically derive the private keys in a ...


3

exodus allows you to backup your private keys (look here). so if exodus will stop their service and you do not want to use exodus anymore (or maybe you can not) you can import your private keys in an other wallet and will not loose any funds.


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