<p>If miners delete the blocks data, someone can fool them by sending a transaction that spends money it shouldn't be able to. In principle, some of them could do that and trust the other miners to validate transactions, but the more people do that, the more the whole network is vulnerable to fraud.</p>

<p>The same can be said for non-miners. If you don't run a full node, you're not actually running Bitcoin, but trusting people that run it to verify transactions for you.</p>

CC BY-SA 3.0
2018-03-14T10:37:22.807Z
2018-03-15T02:01:24.840Z
2018-03-15T02:01:24.840Z
Osias Jota
<p>Of course that's possible. A miner may be using SPV / keeping only the block headers*. The downside of this is that such a miner won't be able to include transactions of people s/he doesn't trust (i.e. not a trustworthy friend of the miner)</p>

<p>If that miner wants to take risk, s/he can verify the transactions that were relayed to him using online block explorers.</p>

<p>*: A miner doesn't even need to keep block headers. If he knows the previous block's hash, timestamp and network difficulty, that's enough.</p>

CC BY-SA 3.0
2018-03-30T18:22:40.657Z
I'd like to vote this answer up but I can't cause I have no reputation. One question, what is SPV? If you can please vote up my question.
Alejandro Veintimilla
CC BY-SA 3.0
2018-03-31T05:48:16.017Z
https://bitcoin.stackexchange.com/a/4651/38618
MCCCS
CC BY-SA 3.0
2018-03-14T14:12:17.697Z
2018-03-14T14:12:17.697Z
MCCCS
<p>I am wondering if all bitcoin miners need to be full nodes. Or is it possible for a miner to just download all the blockchain once, do all necessary computations to start mining and then delete the complete blockchain and only work on the "last blocks". I.e can a miner don't be a full node?</p>

<p>This is not a duplicate question.</p>

CC BY-SA 3.0
2018-03-14T07:59:02.667Z
no - he can't. A miner would want to receive transactions from other clients, to create new blocks. He would need to verify these tx, and therefor the blockchain is required.
pebwindkraft
<miner-configuration><full-node>
Can a miner just download the blockchain once and then delete it (don't have a full node)?
Alejandro Veintimilla
# Can a miner just download the blockchain once and then delete it (don't have a full node)?

(Asked by: username_0 on 2018-03-14)

I am wondering if all bitcoin miners need to be full nodes. Or is it possible for a miner to just download all the blockchain once, do all necessary computations to start mining and then delete the complete blockchain and only work on the "last blocks". I.e can a miner don't be a full node?

This is not a duplicate question.

**Tags:** miner-configuration, full-node

> **Comments:**
> **username_1**: no - he can't. A miner would want to receive transactions from other clients, to create new blocks. He would need to verify these tx, and therefor the blockchain is required.  

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## 2 answers

### Answer by username_2 on 2018-03-14. Score: 0 | Accepted answer

If miners delete the blocks data, someone can fool them by sending a transaction that spends money it shouldn't be able to. In principle, some of them could do that and trust the other miners to validate transactions, but the more people do that, the more the whole network is vulnerable to fraud.

The same can be said for non-miners. If you don't run a full node, you're not actually running Bitcoin, but trusting people that run it to verify transactions for you.


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### Answer by username_3 on 2018-03-14. Score: 0

Of course that's possible. A miner may be using SPV / keeping only the block headers\*. The downside of this is that such a miner won't be able to include transactions of people s/he doesn't trust (i.e. not a trustworthy friend of the miner)

If that miner wants to take risk, s/he can verify the transactions that were relayed to him using online block explorers.

\*: A miner doesn't even need to keep block headers. If he knows the previous block's hash, timestamp and network difficulty, that's enough.

> **Comments:**
> **username_0**: I'd like to vote this answer up but I can't cause I have no reputation. One question, what is SPV? If you can please vote up my question.  
> **username_3**: https://bitcoin.stackexchange.com/a/4651/38618  

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