<p>In pruning mode, you still have to download and verify the entire blockchain (so you still get the security of having done that).  However, as it downloads new blocks, it deletes old ones, so that you never have to store more than 550 MB.</p>

<p>It saves storage space, but not bandwidth or CPU.</p>

CC BY-SA 3.0
2018-02-04T20:30:05.987Z
2018-02-04T20:30:05.987Z
Nate Eldredge
<p>Pruning just means it doesn't store the blocks forever, but it still must download them all at least once to verify the chain and track the unspent outputs which form the UTXO set. Once the blocks are downloaded and verified then they can be automatically deleted</p>

CC BY-SA 3.0
2018-02-04T20:36:33.160Z
How does it verify old transactions though if it deletes old blocks?
2523454
CC BY-SA 3.0
2018-02-04T20:37:08.577Z
It verifies them and *then* deletes them
meshcollider
CC BY-SA 3.0
2018-02-04T20:31:49.170Z
2018-02-04T20:31:49.170Z
meshcollider
<p>I set up my first bitcoin node and I'm a little confused with it.</p>

<p>So, I am trying to setup a pruned node - which from my understanding is very useful if you just need your application to verify transaction/read blocks/lookup TXIDs.</p>

<p>I added:</p>

<pre><code>prune=550
</code></pre>

<p>to my bitcoin.conf, and started up daemon again.</p>

<p>However, I am now confused. I ran bitcoin-cli getinfo and got this:
<a href="https://i.sstatic.net/KK0g8.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/KK0g8.png" alt="enter image description here"></a></p>

<p>It seems like it is still downloading the entire blockchain, and its downloading oldest blocks to newest.</p>

<p>Did I do something wrong? Isn't the point of pruning just to download recent blocks to verify transactions? Please someone fill me in...</p>

<bitcoin-core><bitcoind>
Why is my pruned node downloading old blocks?
2523454
# Why is my pruned node downloading old blocks?

(Asked by: username_0 on 2018-02-04)

I set up my first bitcoin node and I'm a little confused with it.
So, I am trying to setup a pruned node - which from my understanding is very useful if you just need your application to verify transaction/read blocks/lookup TXIDs.
I added:
prune=550

to my bitcoin.conf, and started up daemon again.
However, I am now confused. I ran bitcoin-cli getinfo and got this:

It seems like it is still downloading the entire blockchain, and its downloading oldest blocks to newest.
Did I do something wrong? Isn't the point of pruning just to download recent blocks to verify transactions? Please someone fill me in...

**Tags:** bitcoin-core, bitcoind


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## 2 answers

### Answer by username_2 on 2018-02-04. Score: 3 | Accepted answer

Pruning just means it doesn't store the blocks forever, but it still must download them all at least once to verify the chain and track the unspent outputs which form the UTXO set. Once the blocks are downloaded and verified then they can be automatically deleted

> **Comments:**
> **username_0**: How does it verify old transactions though if it deletes old blocks?  
> **username_2**: It verifies them and *then* deletes them  

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### Answer by username_1 on 2018-02-04. Score: 1

In pruning mode, you still have to download and verify the entire blockchain (so you still get the security of having done that). However, as it downloads new blocks, it deletes old ones, so that you never have to store more than 550 MB.

It saves storage space, but not bandwidth or CPU.


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