– Help visualize all the Gulden nodes

What is cooler than knowing that Gulden is a growing network of nodes? Well seeing those nodes is way cooler than only knowing that they are there. A Slack user I’ve been chatting with, named Sebastiaan Pasma has such an overview and it looks totally great. His website gives a visual overview of the nodes connected to each other for the Gulden Blockchain.

The problem Sebastiaan faces is that he only gets data from his own nodes running, thus he cannot get a complete overview of the Gulden Blockchain. His server is maybe connected to 200 other nodes, but those 200 nodes are also connected to other nodes. To make a long story short: Sebastiaan needs more peer information from as many nodes as possible. If you’ve got a node running you can help him really quickly.

So where do you start? Well, first you have to have your node up-and-running. You can read it here how to create a Gulden node. Second it is wise to read my previous blogpost about development for the Gulden Blockchain.

After having thos up-and-running correctly there are a few steps you need to do in order to send your data to the website.

Step 1: Install CURL

We’re going to send the Peer data via the cURL-command to the GuldenNodes endpoint. Therefore obviously cURL needs to be installed. Therefore you need to be logged in on your server and type the command

sudo apt-get install curl

If the installer asks for some confirmations press “Y”.

Step 2: Post peerinfo to GuldenNodes endpoint

To post the peerinfo to the endpoint type in following:

/guldenserver/Gulden-cli -datadir=/guldenserver/datadir getpeerinfo | curl -X POST -H "Content-Type:application/json" -d @-

The first part /guldenserver/Gulden-cli is the location of my Gulden-cli application. (I’ve updated the Gulden application so the paths from the pervious blogpost don’t exactly match anymore).
The second part -datadir=/guldenserver/datadir is the location of my Gulden data directory, again, this can be different from yours.
The third part is the command getpeerinfo. This is the information we want to send to

The pipe-sign means: Anything before this sign is used as input for the next function.
The fourth part is the cURL POST. To post the data from “Getpeerinfo” to GuldenNodes.

If everything went well you should see some nice ASCII-art:

Woah, 19 new node updates!

If you don’t see this, don’t try to continue. Please contact me via the Gulden Slack Channel. Make sure you have the correct path to your application and your datadir. That is where probably your error is.

Step 3: Create a cron-job to automate sending data

In the previous step we posted data of our peers to the website. But it would be really awesome if this data gets send let’s say every 30 minutes. Therefore we can create a so-called cronjob.
First create a shell script in your /guldenserver directory

nano /guldenserver/

Paste the working commandline from step 2 in the file and save the file.

/guldenserver/Gulden-cli -datadir=/guldenserver/datadir getpeerinfo | curl -X POST -H "Content-Type:application/json" -d @-

Chmod +x the file so that it can be executed by Cron:

chmod +x /guldenserver/

And add a row in crontab

crontab -e

When asked which editor to use; pick your favorite editor (mine is nano). And paste the line below in the crontab -e configuration:

*/30 * * * * /guldenserver/

This runs the file every 30 minutes. The content of the file is the POST to

If you want to check if your cron setup is correct than go to the croncheck page on ( Fill in your IP-address and see if your Cronjob works correctly. It should look something like this:

Optional: Step 4

You can make a few changes to your Gulden.conf file. Thinks I’ve changed:

Maxconnections makes sure my node doesn’t make more than 20 simoultanious connections, something I need to keep the memory and CPU-usage at an acceptable level
MaxUploadTarget makes sure the Gulden application tries to not send/receive more than XXX MB per day.

Sebastiaan is currently working further on his website. He will add more features to the website so that you can see nice stats about your node etc.

Update 09-09-2017

Since Sebastiaan created this endpoint and I’ve written this blogpost we see a tremendous increase in visible Gulden Nodes. We can conclude that sending this information to the GuldenNodes endpoint gives us a more detailed overview of the Gulden Network.

Buy me and/or Sebastiaan a beer

If you found this article interesting or if it helped you in any way – please keep in mind that it took me quite some time to collect the above data and write it down in a blog post. It would be very much appreciated if you’d buy me a beer when it saved you some time or if you think this post was interesting ? Please consider a donation.

Me: GHxng2LZte7rbqSxcD3rNFuZmg7eEPuXq5
Sebastiaan: GSjCYX2Fn4LSH6YVYhsiEkqCaMRdTzRZEd