Bitcoin Core's prune node. Please help to use it safely.

[OcTradism]

From this:

it requires 284 GB as minimum free space.

that is the minimum space required if you want to run it as a full node storing the entire blockchain history. otherwise you can run bitcoin core as a pruned node where you only store the most recent blocks alongside chainstate and that can reduce the size to a much smaller value (550 MB).

I don't want to waste my storage space for the wallet because I am not going to run the Bitcoin Core full node, so I try to apply the advice.
When I run the wallet, I see the option:
- Discard blocks after verification, except most recent 2 GB (prune).
What should I do?
Choosing that option or not?

I guess the answer is choosing it.

Next, can I still recover my wallet on the other devices (if I have private key) with that prune node?

Last, are there options to set up the allocated space for that prune node (more than 2 GB but less than the required one for full node > 500 GB)?

Thank you.

[ranochigo]

From this:
When I run the wallet, I see the option:
- Discard blocks after verification, except most recent 2 GB (prune).
What should I do?
Choosing that option or not?

Yes. That is to prune the wallet.

Next, can I still recover my wallet on the other devices (if I have private key) with that prune node?

Yes. The private key is the only thing required for you to access your addresses. As long as you have your private keys, you can import it into another wallet and use it.

Last, are there options to set up the allocated space for that prune node (more than 2 GB but less than the required one for full node > 500 GB)?

Yes. You can use bitcoin.conf and use prune=X parameter to customize. The X is the space in MB. It doesn't really affect how much of a space you've allocated unless there is a major block reorganisation and that the blocks needs to be rolled back or if you want to import another wallet.dat.
The main caveat with pruning is that you'll need to synchronise the whole wallet again if you want to import a wallet.dat that was last synchronised beyond your range of pruned blocks.

[OcTradism]

The main caveat with pruning is that you'll need to synchronise the whole wallet again if you want to import a wallet.dat that was last synchronised beyond your range of pruned blocks.

It means with full or prune wallet, I always have to sync my wallet with network (that always take very long period, days or weeks).
More seriously, with prune wallet, I have to resync it from scratch if I import with a wallet.dat as you said.

Your reply raises a question for me that can I fastly sync my wallet (with prune or full node) with a blockchain snapshots? I saw that technical term with altcoin but for bitcoin, I don't know.

[nc50lc]

If you have enough storage space, I suggest you not to prune.
Pruning will probably give you more issues than benefits in the future like you'll have to re-download to verify the entire blockchain if something happened to your wallet file, when you need to rescan or in case some of your blk files got corrupted.

Next, can I still recover my wallet on the other devices (if I have private key) with that prune node?

Can't tell exactly (could be wrong) but, AFAIK if you don't have the blocks which contains the necessary UTXO of that wallet file with outdated history, you'll have to download/verify from scratch.

Last, are there options to set up the allocated space for that prune node (more than 2 GB but less than the required one for full node > 500 GB)?

According to the test by minefarmbuy, you can set it up to 99GB; but if you're willing to allocate 99GB, you may as well consider disabling pruning.

-snip-
Looks like 99GB is max for a pruned node.

[OcTradism]

If you have enough storage space, I suggest you not to prune.
Pruning will probably give you more issues than benefits in the future like you'll have to re-download to verify the entire blockchain if something happened to your wallet file, when you need to rescan or in case some of your blk files got corrupted.

For now, I can run a full node with Bitcoin Core with my available storage space, but I doubt that the space to store the whole blockchain history will be required much more when time goes. Especially over time bitcoin has become more widely accepted and transacted so maybe the space storage required to save the whole blockchain per year will increase over years. Do I imagine it right?
For instance:
- 100 GB for the year 2019
- 150 GB for the year 2020
- 200 GB for the year 2021
If it is the story, then I can not manage to sync my wallet as a full node with bitcoin network.

[Jet Cash]

You don't have to run a node 24/7, and you can keep the blockchain and wallet data on an external drive. This means that if you are using a notebook in a public space, and it is stolen, you won't lose your coins if the drive is not connected. You should always back up your wallet data and the blockchain regularly as well. An extra USB drive is fairly cheap these days, and it could save you having to download the whole chain in the future.

[LoyceV]

maybe the space storage required to save the whole blockchain per year will increase over years.

Obviously, the blockchain increases in size with every new block. But the increase doesn't happen at exponential speed, since blocks have a maximum size, and most blocks are quite full already.
So that means you can expect more or less linear growth for the coming years.

[OcTradism]

maybe the space storage required to save the whole blockchain per year will increase over years.

Obviously, the blockchain increases in size with every new block. But the increase doesn't happen at exponential speed, since blocks have a maximum size, and most blocks are quite full already.
So that means you can expect more or less linear growth for the coming years.

I got it. Thank you for lifting me out of the mess.

An extra USB drive is fairly cheap these days, and it could save you having to download the whole chain in the future.

I don't think USB drives can help to store (not enough GB capacity) the whole blockchain database after I sync my wallet today.

This means that if you are using a notebook in a public space, and it is stolen, you won't lose your coins if the drive is not connected.

It is a key, I have never used my computer in which I store my crypto wallets in public space. The device I use everyday does not store any wallets or private keys inside.

[nc50lc]

For now, I can run a full node with Bitcoin Core with my available storage space, but I doubt that the space to store the whole blockchain history will be required much more when time goes. Especially over time bitcoin has become more widely accepted and transacted so maybe the space storage required to save the whole blockchain per year will increase over years.
Do I imagine it right?

Quite, but the rate didn't get higher since 2017 and it will stay like that except if the devs/community decided to increase the block size limit.
It'll start with ±250GB for 2020, then about +50-60GB per year, can be higher depending on the number of SegWit data.

By the time the blockchain reached 400GB, a 1TB HDD would be less than $20, in fact, you can get some 2nd-hand units in that price range today.

If it is the story, then I can not manage to sync my wallet as a full node with bitcoin network.

I suppose you've already researched the other options like SPV clients or hardware wallets,
so why not use the alternative wallets instead since you've mentioned that you're not going to run a full node?

[ABCbits]

I don't think USB drives can help to store (not enough GB capacity) the whole blockchain database after I sync my wallet today.

USB is just the interface. He could mean USB HDD drives which is cheaper than USB flash drive or USB SSD drive.

By the time the blockchain reached 400GB, a 1TB HDD would be less than $20, in fact, you can get some 2nd-hand units in that price range today.

I wouldn't recommend using 2nd-hand or refurbished HDD for intensive tasks (e.g. running full node client).

[naska21]

Next, can I still recover my wallet on the other devices (if I have private key) with that prune node?

IMO, yeah you can, to be on the safe side  backup  both chainstate and blocks folder and when needed copy them to second device.

[Husna QA]

-snip-
If it is the story, then I can not manage to sync my wallet as a full node with bitcoin network.

You can move the Bitcoin Core data directory to a larger hard drive. It can be seen in the following article:
https://bitzuma.com/posts/moving-the-bitcoin-core-data-directory/
Note: Don't forget to backup your wallet first.

[HCP]

Your reply raises a question for me that can I fastly sync my wallet (with prune or full node) with a blockchain snapshots? I saw that technical term with altcoin but for bitcoin, I don't know.

To answer this specific question... the short answer is "No".

Significant advances were made in a few previous versions of Bitcoin Core that made "snapshots" slower than just syncing blocks normally.

[Abdussamad]

The correct way to backup your bitcoin core wallet is to use the backup wallet option in the file menu. Storing copies of private keys may not suffice since your coins will frequently move to new private keys whenever you spend. Storing a copy of the master private key is also not foolproof since it doesn't contain other information about your wallet like the derivation path that was used. So best to use the option provided in the file menu.

[lankymanx]

Oh my goodness, ive never read something from an awesomely written wallet such as Bitcoin core, which is so hella confusing - seriously.

The welcome screen as follows:

The first piece of text from "As this..." is all good up until "...2009 when Bitcoin initially launched."
The rest is not straight forward at all, especially if u are a regular user storing coins and you are not technically minded.
You would not know why the blockchain is re-downloading or all of a sudden u have 0 balance.

I mean really, the part which starts with "...and may expose hardware problems with your computer that had previously.." i mean really, this is badly and horribly worded - its ridiculous.

Very 0.18 never had this nonsense.

I can see where they are going with this, having to allow to store as much data on disk for the wallet to work and reflect correct details, but it needs to be explained properly if there is going to be as much text as there currently is on the welcome screen.