Questions about pruned nodes.

[seoincorporation]

I was reading about pruned nodes, and want to use one for a personal project, but i have some questions, from what i understand a pruned node is the same software but we add the prune factor in the config file.

As a reference I'm using this guide: https://www.vpsbg.eu/docs/how-to-install-a-full-or-pruned-bitcoin-node

Firstly, navigate to the Bitcoin website and download the latest version:

wget https://bitcoin.org/bin/bitcoin-core-22.0/bitcoin-22.0-x86_64-linux-gnu.tar.gz

After downloading the file, you will need to extract its content:

tar xzf bitcoin-22.0-x86_64-linux-gnu.tar.gz

Next, execute the following command in order to begin the installation process:

cd bitcoin-22.0/bin && install -m 0755 -o root -g root -t /usr/local/bin *

Now comes the most integral part - choosing whether you want to run a full or a pruned Bitcoin node. To run the full version you can simply type the following command, which will begin synching with the blockchain:

bitcoind -daemon

Depending on your connection’s speed and the size of the database at the time of you downloading it, the process might take up to a number of days, given that the blockchain is constantly expanding.

If, however, you would like to run a pruned node, you will have to create a special configuration file, which you can do with this command:

touch /root/.bitcoin/bitcoin.conf

Next, open the newly generated file in any text editor and insert the following line:

prune=550

Do not forget to save the file! After that you can again begin to sync with the blockchain using the same command as that for a full node:

bitcoind -daemon

Additionally, you can check and monitor how the syncing process is going with this command:

bitcoin-cli getblockchaininfo | grep verification

You will be presented with something that will look like so:

"verificationprogress": 0.7052169307479244

Remember that the ‘verificationprogress’ parameter does not need to reach 1.0000, as a value close to 0.9999 would indicate that the node is already synced.

That's it! You should now have a fully functional Bitcoin node!

And my questions are:

Why do we use prune=550? what does that 550 mean? Can we change that value?

How much space i need in my hard disk for the pruned node?

[Mia Chloe]

Prune 550 simply means you are going to be downloading but storing 550mb worth of block chain data. And by default it means you will be  syncing the whole blockchain but retaining the most recent block chain data of 550mb size.
It is actually customizeable but mainly to higher sizes of 1GB or even more. Running a prune node is usually done when you don't have sufficient disk space if not i would advise you download and sync totally with the block chain from Genesis block till date.

So if you are running a prune node make sure you storage is above  the customized storage for example if you are running prune 550 , it is recommended you have up to 300mb of disk space free  to avoid lagging or syncing issues relating to low storage. Also make sure you have a good RAM of at least 4Gb or even more so lagging won't be an issue also.

[Amphenomenon]

Also make sure you have a good RAM of at least 4Gb or even more so lagging won't be an issue also.

It should be noted that using 4GB Ram for syncing makes it slower I.e the higher the Ram used for syncing the faster synchronization, the Ram size as more effect in your syncing speed than your disk and so if your disk size meet the requirements to run node, you can try to increase your RAM in order to improve the whole process

In order to improve the syncing process, even the entire bitcoin Core performance, after setting your prone size use:
 

Code:

dbcache = half of the size of your ram in mb

[CHALLENGE] Run A Bitcoin Node: 14 Days To 14 Merits
In case you might face any challenges during setting your node you can check that thread, since there other members running a prune node

[hosseinimr93]

Prune 550 simply means you are going to be downloading and syncing 550mb worth of block chain data.

This is wrong. You have to download the entire blockchain, even if you run a pruned node.
If you set the prune limit to x GB, you would download the entire blockchain, but store only x GB of that. That doesn't mean you only download x GB of the blockchain.

[Mia Chloe]

Prune 550 simply means you are going to be downloading and syncing 550mb worth of block chain data.

This is wrong. You have to download the entire blockchain, even if you run a pruned node.
If you set the prune limit to x GB, you would download the entire blockchain, but store only x GB of that. That doesn't mean you only download x GB of the blockchain.

Thanks for the heads up had wrong phrasing there.
Now corrected.

[Yamane_Keto]

Why do we use prune=550? what does that 550 mean? Can we change that value?

How much space i need in my hard disk for the pruned node?

pruned nodes download all the blocks, but delete the raw block once you finish building the databases and verifying the validity of the blocks.

The number 550 indicates the minimum, which is the value of two days of blocks. Assuming that a block is created in an average of 10 minutes, this means 288 blocks, 550/288 = ~2MB.

[PX-Z]

This is wrong. You have to download the entire blockchain, even if you run a pruned node.
If you set the prune limit to x GB, you would download the entire blockchain, but store only x GB of that. That doesn't mean you only download x GB of the blockchain.

Does it mean that the downloaded data will only be 550 mb, but will start to download the genesis block then will delete the later block data replacing the new downloaded one so on and so forth? Or it will really download the whole current size of bitcoin blockchain then will delete the old block data and retain the new one 550 mb in size.

Another questions, will you still called the pruned node as full node? What's the difference of it on full node aside from saving it on smaller data? How about the weigh of "supports" on the bitcoin blockchain, does it matter?

[hosseinimr93]

Does it mean that the downloaded data will only be 550 mb, but will start to download the genesis block then will delete the later block data replacing the new downloaded one so on and so forth? Or it will really download the whole current size of bitcoin blockchain then will delete the old block data and retain the new one 550 mb in size.

A pruned node starts from downloading the genesis block, but it prunes old blocks and stores the most recent blocks and the UTXO set.

Another questions, will you still called the pruned node as full node? What's the difference of it on full node aside from saving it on smaller data? How about the weigh of "supports" on the bitcoin blockchain, does it matter?

When it comes to validating transactions and blocks, there is no difference between a pruned node and a full nodes.
With both, you validate transactions and help the network to be more decentralized.

The downside of a pruned node is that you would have to redownload the blockchain, if you load a new wallet

[PX-Z]

The downside of a pruned node is that you would have to redownload the blockchain, if you load a new wallet

Is this included the imported wallet file too?

Thanks for the answers btw, i will rethink to run a node again but pruned only as i don't have enough space for it, at least 100gb is enough i think.

[hosseinimr93]

The downside of a pruned node is that you would have to redownload the blockchain, if you load a new wallet

Is this included the imported wallet file too?

Yes.
If you run a prune node, you would have to redownload the blockchain whenever you need to reindex or rescan the whole blockchain.
If pruning is enabled, you can only rescan the blocks that are not pruned yet and still exist in your hard drive.

[Yamane_Keto]

The downside of a pruned node is that you would have to redownload the blockchain, if you load a new wallet

Is this included the imported wallet file too?

You can avoid re-scanning the blockchain by importing private keys using

Code:

importprivkey [key] [label] false

In this way, you will avoid rescan, or by making sure of the blocks you need by adjusting prune=550 to the number of blocks you need, as I mentioned above (550 is enough blocks for two days only).

[seoincorporation]

Thanks for your answers hosseinimr93 Yamane_Keto PX-Z Amphenomenon, especially to hosseinimr93, the information provided was priceless.

If we have to download/sync the full blockchain then it isn't cool at all, i was thinking for pruned nodes we only had to sync the last blocks, and that would be cool and fast. But i was wrong it would take the same time to have a full node as a pruned one.

And the resync on the new wallet is something that i don't like at all, it even sounds like a nightmare.

I will leave the thread open for those who have more questions about this kind of nodes.

[LoyceV]

As a reference I'm using this guide: https://www.vpsbg.eu/docs/how-to-install-a-full-or-pruned-bitcoin-node

touch /root/.bitcoin/bitcoin.conf

This is bad advice! You should never give root access to anything that doesn't need it.

Here's what I use on my server:

Code:

~/bitcoin-26.0/bin/bitcoind -maxuploadtarget=500000 -dbcache=4096

Note that 4 GB dbcache is low for the IBD, but I don't want to give it 16 GB continuously. Normal file cache can handle it anyway. I simply extracted the compressed file in a home directory, and run it with user permissions. There's no need to edit config files, all options can be added to the starting command.
The 500 GB upload target is a daily limit, only set to prevent crazy things, but never came close to that amount.

Why do we use prune=550? what does that 550 mean? Can we change that value?

It's the minimum amount. I've used 100000 in the past, that's enough to load any wallet.dat that hasn't been used for a year.

How much space i need in my hard disk for the pruned node?

You'll need another 11 GB for chainstate, so if you prune to 550 MB, 12 GB is the minimum. And this number keeps growing.

If we have to download/sync the full blockchain then it isn't cool at all, i was thinking for pruned nodes we only had to sync the last blocks, and that would be cool and fast. But i was wrong it would take the same time to have a full node as a pruned one.

You could download someone else's pruned blockchain, but don't do this. The only way to be absolutely sure your data is correct is to sync from scratch. Verify, don't trust.

And the resync on the new wallet is something that i don't like at all, it even sounds like a nightmare.

Note that you don't need to resync if you create a new wallet. You may need to resync if you load an old wallet.

[SquirrelJulietGarden]

Prune 550 simply means you are going to be downloading but storing 550mb worth of block chain data. And by default it means you will be  syncing the whole blockchain but retaining the most recent block chain data of 550mb size

Running a Bitcoin node, either Full node or Prune node, you will have to do IBD (Initial Blockchain Download) and this step takes most of your time.

With Full node, you will store the whole blockchain after IBD and top it up with new blocks' data.

With Prune node, you will store latest blocks' data till your prune node size, that is set up by yourself.

Bitcoins' Initial Block Download.