Bitcoin Forum

What would happen if all block chain copies get deleted at one time?

There are full members of the community and some are the regular users who have the full software keep the blockchain and know something
about the system they are never going to delete the blockchain.

Bitcoin would stop.

You need the previous block to "build upon", without which it wouldn't work.
Another genesis block would need to be created...

It's most likely that LTC would just take over...

Never thought of that and don't think it can happen, let's see what Bitcoin Gurus has to say about this.

the truth is it's not possible but  nothing is impossible for man.....

There are copies out there saved.   It would not have to start over but might lose some transactions in theory.   But I agree it is a impossible thing to happen.   

Why would all the copies be deleted?

And secondly, they would have to be deleted simultaneously and no one can object.

Imagine it's impossible due to the number of blockchain backups. Even if there was a virus out there corrupting blockchain files, there are always going to be offline copies on harddrives / USBs etc.

Since the blockchain is the only place where all bitcoin balances are stored, a deletion of all blockchain copies would mean that no bitcoins exist anymore, of course.

We don't know how long humankind will continue to exist (at the moment, we're working diligently to minimize the time of our presence on this planet), but I suspect that unless a truly catastrophic event exterminates us, some copies of the blockchain will be preserved on hard disks or other media in well-protected places or even in scrapped computers on landfills somewhere.

So I won't say "it can't happen" but it is an extremely unlikely event, and when that event happens, nobody would be left to bother, so why should we bother now?

Onkel Paul

Looking at checkpoints file, I'd guess everyone'd start at the genesis block (hard-coded in the client) until we get to block 11111, the earliest block acting as a checkpoint. I'm not sure what'd happen when a client reaches that block, but since difficulty isn't hard-coded, we'd reach block 11111 pretty quickly... I'd guess it'd either cause "misbehavior score" to increase, resulting in clients banning themselves, or the client notices this and presents some kind of "your data's corrupted" message and stops trying to process blocks until the client's restarted.

There are so many backups of the blockchain, we would never have to start over. The problem is when we have different copies with different block heights, which one should we choose to be the main chain.

If ever the blockchain is deleted simultaneously (which is very unlikely to happen), there will be no bitcoin, of course. But if someone ever backed up a copy of the chain, we can use that as our main chain in order to continue the blockchain.

It may be very improbable, but there's always a possibility (like some very tragic or catastrophic event) for things like this to happen.

Ahh, I wasn't aware that the genesis block was hard coded into the client.

Whatever the case, resetting Bitcoin would destroy all companies involved in it, and remove the likelihood of anyone trusting Bitcoin ever again.

Yup. It's in chainparams.cpp and even includes Satoshi's message:

        const char* pszTimestamp = "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks";
        CTransaction txNew;
        txNew.vin.resize(1);
        txNew.vout.resize(1);
        txNew.vin[0].scriptSig = CScript() << 486604799 << CScriptNum(4) << vector<unsigned char>((const unsigned char*)pszTimestamp, (const unsigned char*)pszTimestamp + strlen(pszTimestamp));
        txNew.vout[0].nValue = 50 * COIN;
        txNew.vout[0].scriptPubKey = CScript() << ParseHex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef3 8c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f") << OP_CHECKSIG;
        genesis.vtx.push_back(txNew);
        genesis.hashPrevBlock = 0;
        genesis.hashMerkleRoot = genesis.BuildMerkleTree();
        genesis.nVersion = 1;
        genesis.nTime    = 1231006505;
        genesis.nBits    = 0x1d00ffff;
        genesis.nNonce   = 2083236893;

        hashGenesisBlock = genesis.GetHash();
        assert(hashGenesisBlock == uint256("0x000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f"));
        assert(genesis.hashMerkleRoot == uint256("0x4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b"));

The source is really well-explained. I was surprised. I only just finally started to really look through it after 3 or 4 years... It's massive (relative to the tiny little things I've done in a short time), though.

It would be an unusual scenario to say the least
I would assume it would resolve and restart from the next longest chainstate someone has a copy of
That or a fork if the main chain broke for some weird reason or other (not likely to happen again) unless some new software comes out that makes its own sidechain.

@ Kluge thats neat thanks for sharing.

There are almost 7000 full nodes https://getaddr.bitnodes.io/, meaning there are at least that number of full copies of blockchain distributed around the world. So I wouldn't be worried about the situation you described to happen.

Govts or Bankers might choose to corrupt them.

And at least you and me we have another copy of it  :D :D

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OP, It's very difficult to get all copies deleted... keep in mind that for example in my case I have periodic copies from all the blockchain and wallets on many USB devices... so if other people do the same, we have at least two more blockchain copies  :P

I've never though about that. But it's 99'9999^99% impossible, wallets and blockchain copies can't disappear like magically  ::)

The advantage of having a distributed ledger is that there are multiple copies of the block chain. So it is highly unlikely that they will all get deleted at the same time.

This might be a problem with fiat banks - what happens when all copies of their ledger get corrupted at the same time.  ;D

I think there are near no ways to occur that all block chain copies get deleted; since there are lots of mirror.

if this happens, then all accounts using blockchain.info would have disturbed the contents walletnya least be involved subject, so I thought, all of the customer account data stored blockchain.info very safe on that is, until now have not heard any problems from blockchain .info, both the sending and receipt of bitcoin, I hope this can last very long ...  8)

Then I'd implement the final step in my plan -- broadcast the difficulty 1 sidechain I've been working on this whole time, whose only difference is I've skimmed off about 100,000 BTC to my own address.

the same as if all bank backup of customer's data happens to be destroyed: we start again from 0, with no idea about the previous status of the accounts.

But it is 100x more unlikely such thing happens with BTC because it is decentralized

Well, simple. Bitcoin is gone forever if block chain get deleted... but is it even possible?

EMP strikes knocking out power to the entire world wouldn't do it, so no, not really. I hear there's a blockchain in space being worked on, too.

So if that happens, where can we get help so that we can get our btc back?

If something catastrophic happens and wipes out data all over the world you're going to have bigger things to worry about.

EMP would not even affect the existing copies of the blockchain as it would only make the computers unusable, it would not delete the information contained on the computers.

This plus the fact that there are many computers (some of which likely are running as a full node - a computer that will contain the full block chain) that are somehow protected from EMP via shilds

If there is a catastrophic event causing a major power outage or internet outage, bitcoiners within the region affected will not be able to spend their bitcoin until they have both power and internet.

But still the historical transactions won't be affected.