Is it possible to give a friend blockchain backup?

[Oshosondy]

I have been thinking of this for a while now, I think this will be the best place to get answer to this question. Normally is it possible for me to download the whole bitcoin blockchain just like in bitcoin core but in a way I can share people around me the back up? In my area, no free wifi, buying data is very expensive which will not be a good alternative for someone to download the whole blockchain. But instead like 10 or more of us or people that are interested around me can request for the whole blockchain already downloaded and backup in a way to just use it to setup a bitcoin core wallet easily, instead of doing it individually. Is there a way out.

[jackg]

Theoretically and realistically yes...

You'd have to give them a copy of the blocks and the chainstate, they'd still have to do the syncing process afaik (or they might just need to rescan with a new wallet file) either way it saves buying excess data.

I'm not sure also if blockstream would be a cheaper option for you. https://blockstream.com/satellite/

I think they're stuff is similar to the outernet and I remember equipment should cost around $20-100 (depending on your postal service obviously).

[Abdussamad]

you can't do the initial block download over the satellite connection.

[Oshosondy]

Do you have any particular reason to use Bitcoin Core or download whole Blockchain?

I like to run a full client wallet, no need to rely on any server to connect to nodes because bitcoin core runs the full nodes without connecting to any server. Also, I want to know more about bitcoin, bitcoin core is the official bitcoin wallet that was created by Satoshi Nakamoto which should not be left out.

[PrimeNumber7]

From a technical perspective, you can share copies of the blockchain, but you will need to trust the person providing the copy.

If data is expensive in your area, I would suggest using a light wallet such as Electrum or Blue Wallet (for mobile). Electrum will require you to use much less data than a full node requires, and you will lose privacy and security only incrementally.

[pooya87]

Also, I want to know more about bitcoin

the idea in bitcoin is that the user doesn't have to rely on anybody else (to avoid centralization and for security reasons). instead they verify everything themselves. that means verifying from block #1 until the 600k+ blocks that are so far mined.
so your idea only works if the purpose was purely to save on data costs for downloading the blockchain. if bitcoin core has the option to verify the local blockchain and if they do that from the start and build the chainstate themselves this could be a viable option.

[Oshosondy]

If you're the only one who thought about it, you could set up Electrum Server and let your friend and yourself (from other device) connect to your Electrum Server.
It's more efficient than running multiple full nodes.

This is a good advice. Thank you for your explanation, I will make use of electrum server, but do you have a guild/article about how I can set up electrum server.

Personally i disagree with calling it official Bitcoin wallet because decentralized nature of Bitcoin, another word such as reference bitcoin wallet might be better.

You are totally right, bitcoin was created by Satoshi Nakamoto, creating bitcoin without creating bitcoin wallet can not make bitcoin of any value, which means bitcoin can not exist without creating bitcoin wallet, that was why he created bitcoin QT, but for now, because bitcoin is decentralized, bitcoin has no official wallet, but bitcoin QT was the first. I totally agree.

[joniboini]

but do you have a guild/article about how I can set up electrum server.

There are a lot of articles on that topic. You can easily search on Google. There is also a guide on Electrum's Github repository[1] if you want to check it out.

[1] https://github.com/spesmilo/electrum-server/blob/master/HOWTO.md

[HCP]

There are a lot of articles on that topic. You can easily search on Google. There is also a guide on Electrum's Github repository[1] if you want to check it out.

[1] https://github.com/spesmilo/electrum-server/blob/master/HOWTO.md

Did you even look at that guide?

The very first sentence:

This code is now unmaintained. The replacement code for electrum server is ElectrumX

Also, because the linked version (kyuupichan) on that page is now effectively BSV only going forward... You want to use the fork of ElectrumX maintained by the Electrum Devs: https://github.com/spesmilo/electrumx

They have a copy of the docs available here that includes a HOWTO guide and links to an installer and a dockerfile: https://electrumx-spesmilo.readthedocs.io/en/latest/