<p>I've kept the same config file and internal hard drive for my Bitcoin Core datadir for many years. I've updated to numerous new versions.</p>
<p>The other day, I reinstalled Windows on the system drive again. And thus reinstalled Bitcoin Core (v22.0.0) again. When it started up, I pointed it to the datadir on the other disk as usual.</p>
<p>Now I realize that it has deleted all of the blockchain data for the first time ever, leaving only 2 GB. It prunes by default to 2 GB now. And apparently, my config needed to have an explicit rule to tell it to not prune... which it of course didn't.</p>
<p>While I'm glad that I don't have to store all that stupid data anymore, it does make me question why they would enable this by default and actually <em>delete</em> existing data. Has pruning now reached such a level of stability that it's completely &quot;safe&quot; and there is no need to save the full blockchain anymore?</p>
<p>Or am I now running Bitcoin Core in &quot;crippled mode&quot;? Even though I did not actively set it to prune?</p>

CC BY-SA 4.0
2021-11-29T20:53:11.170Z
Bitcoin Core will never prune on its own; it is not default. It must be configured, either through config file, command-lirn arguments, or the GUI settings window, to enable pruning.
Pieter Wuille
CC BY-SA 4.0
2021-11-29T21:04:17.503Z
@PieterWuille No "prune" command in my config.
Randoll
CC BY-SA 4.0
2021-11-29T21:06:07.290Z
Are you using `bitcoind` or `bitcoin-qt`? Have you checked the UI settings (they are separate from bitcoin.conf)? Is something about "prune" logged in debug.log?
Pieter Wuille
CC BY-SA 4.0
2021-11-29T21:13:29.510Z
@PieterWuille `bitcoin-qt.exe`. Yes, the UI settings were and are set to prune at 2 GB, since that's now the default, but the bitcoin.conf is supposed to take precedence over the GUI settings.
Randoll
CC BY-SA 4.0
2021-11-29T21:34:20.053Z
I thought GUI settings override bitcoin.conf, but I'm not entirely sure about that. Still, pruning is *not* the default as far as I know (it's not for me, in either bitcoind or bitcoin-qt, and I don't have any pruning related settings anywhere).
Pieter Wuille
CC BY-SA 4.0
2021-11-29T21:38:37.953Z
@PieterWuille I don't know what to tell you. I have certainly not set up pruning in the GUI.
Randoll
CC BY-SA 4.0
2021-11-29T21:39:45.727Z
I also don't know what to tell you, except that no, pruning is not on by default.
Pieter Wuille
CC BY-SA 4.0
2021-11-29T22:02:49.923Z
@PieterWuille So I have a magical or compromised copy of Bitcoin Core, then?
Randoll
CC BY-SA 4.0
2021-11-29T22:21:02.320Z
It appears I'm wrong. The "first run" dialog, when selecting a filesystem with less than a certain threshold available space, will suggest have pruning enabled by default. If you then click continue without turning it off, that becomes the saved GUI setting for Bitcoin-Qt.
Pieter Wuille
<bitcoin-core>
Bitcoin Core just deleted my 350+ GB of blockchain data?
Randoll
# Bitcoin Core just deleted my 350+ GB of blockchain data?

(Asked by: username_0 on 2021-11-29)

I've kept the same config file and internal hard drive for my Bitcoin Core datadir for many years. I've updated to numerous new versions.

The other day, I reinstalled Windows on the system drive again. And thus reinstalled Bitcoin Core (v22.0.0) again. When it started up, I pointed it to the datadir on the other disk as usual.

Now I realize that it has deleted all of the blockchain data for the first time ever, leaving only 2 GB. It prunes by default to 2 GB now. And apparently, my config needed to have an explicit rule to tell it to not prune... which it of course didn't.

While I'm glad that I don't have to store all that stupid data anymore, it does make me question why they would enable this by default and actually *delete* existing data. Has pruning now reached such a level of stability that it's completely "safe" and there is no need to save the full blockchain anymore?

Or am I now running Bitcoin Core in "crippled mode"? Even though I did not actively set it to prune?

**Tags:** bitcoin-core

> **Comments:**
> **username_1**: Bitcoin Core will never prune on its own; it is not default. It must be configured, either through config file, command-lirn arguments, or the GUI settings window, to enable pruning.  
> **username_0**: @PieterWuille No "prune" command in my config.  
> **username_1**: Are you using `bitcoind` or `bitcoin-qt`? Have you checked the UI settings (they are separate from bitcoin.conf)? Is something about "prune" logged in debug.log?  
> **username_0**: @PieterWuille `bitcoin-qt.exe`. Yes, the UI settings were and are set to prune at 2 GB, since that's now the default, but the bitcoin.conf is supposed to take precedence over the GUI settings.  
> **username_1**: I thought GUI settings override bitcoin.conf, but I'm not entirely sure about that. Still, pruning is *not* the default as far as I know (it's not for me, in either bitcoind or bitcoin-qt, and I don't have any pruning related settings anywhere).  
> **username_0**: @PieterWuille I don't know what to tell you. I have certainly not set up pruning in the GUI.  
> **username_1**: I also don't know what to tell you, except that no, pruning is not on by default.  
> **username_0**: @PieterWuille So I have a magical or compromised copy of Bitcoin Core, then?  
> **username_1**: It appears I'm wrong. The "first run" dialog, when selecting a filesystem with less than a certain threshold available space, will suggest have pruning enabled by default. If you then click continue without turning it off, that becomes the saved GUI setting for Bitcoin-Qt.  

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## 0 answers

