Dev:Run a Testnet Node

This guide will help to set up a node on the nexus testnet. No permission is required to join the testnet and users have complete control of the dedicated node.

The node configuration will differ as per the individual application requirement or amount of transactions generated.

If you need any help on the node specifications for a particular application do contact developer support here.

Prerequisites

• A computer with a minimum of 1 CPU, 1GB RAM, 20GB hard space, Raspberry Pi 4 with 2 GB RAM.
• VPS with 1GB RAM is sufficient for normal usage.
• Ubuntu server 20.04 LTS or Debian 11 for AMD/IA64 or Ubuntu IOT / Raspberry Pi OS 64 bit for Raspberry Pi. (Use any linux distribution of choice, but this guide is tailored for Debian /Ubuntu).
• USB drive or SD card to install ubuntu
• Etcher – To burn the OS image file to USB/SD card
• Putty if you are using ssh via windows

Do not use Ubuntu 22.04 as it has the new version of openssl which breaks compatibility with core.

Testnet Mining Node Links

The testnet mining nodes are listed below:

• http://testnet1.nexus-interactions.io
• http://testnet2.nexus-interactions.io
• http://testnet3.nexus-interactions.io

Testnet Ports

The testnet uses a different set of ports compared to the mainnet. If using a firewall, make sure to open the following ports. Legacy is disabled and the reason RPC port 8336 is not allowed:

7080 - API port 8325 - Mining port, only enable if mining on testnet 8888 - Outgoing node connections

Caption text

Port	Description
7080	API port
8325	Mining port, only enable if mining on testnet
8888	Outgoing node connections

Prepare The Node

Install Ubuntu server 20.04 LTS or distro of your choice, install open-ssh server during the install and once the installation is complete restart the node. SSH in your node and follow the below commands. You can copy the commands and paste it in the terminal using keys CTRL+SHIFT+v.

Update your node:

sudo apt update

Upgrade your node:

sudo apt upgrade -y

Open SSH port before you enable firewall:

sudo ufw allow ssh

Allow API port 7080:

sudo ufw allow 7080/tcp

Allow outgoing connections port 8888

sudo ufw allow 8888/tcp

Allow mining port 8325, only if mining

sudo ufw allow 8325/tcp

Enable firewall:

sudo ufw enable

Check firewall status:

sudo ufw status

Set your timezone:

sudo dpkg-reconfigure tzdata

If you need to change the hostname – Not compulsory if you already set it during the install:

sudo hostnamectl set-hostname <newhostname>

Reboot node:

sudo reboot

We have our computer ready to install the nexus core!

Compiling Nexus Core Install the dependencies required for compiling nexus core CLI. It will take some time to complete depending on your internet speed:

sudo apt-get install -y build-essential libssl-dev libdb-dev libdb++-dev libminiupnpc-dev git

Download the latest nexus core source code, and should only take a few seconds to complete:

git clone --branch merging https://github.com/Nexusoft/LLL-TAO

Change into the source code directory:

cd LLL-TAO

Lastly, run this command to compile from source. This begins compiling the nexus core. Please be patient, as this can take a long time depending on your CPU. Replace the 1 in ‘j1’ to the number of cores / threads for compiling faster. To build on Raspberry Pi with 1 GB of ram you have to enable Swap memory. Proceed after setting up swap:

make -f makefile.cli clean

For x86/IA64 computers use:

make -f makefile.cli -j1 AMD64=1 NO_WALLET=1

For the raspberry pi use:

make -f makefile.cli -j4 ARM64=1 NO_WALLET=1

The output will show “Finished building nexus” on a successful compile.

Testnet Node Configuration

The nexus wallet configuration is kept in a nexus.conf file in ~/.Nexus which is the nexus core directory. Create Nexus core directory (it’s a hidden directory, if you have the directory you can skip this step.):

mkdir ~/.Nexus

Create the nexus.conf file:

nano ~/.Nexus/nexus.conf

Copy the below configuration in the nexus.conf file and change the values denoted by "< >" to suit your setup:

#Nexus testnet config- PLEASE CHANGE TO SUITABLE VALUES
#Set API credentials
apiuser=<username>
apipassword=<password>
#To enable API authentication for testing
apiauth=1
#To enable API remote access
apiremote=1
#To whitelist IP address for API access
llpallowip=<ipaddress>:7080
#To enable multiuser mode: enables more than one user to be logged into the node
multiuser=1
#To enable debug mode
#debug=1
#To enable the daemon mode
daemon=1
#To accept incoming JSON-RPC commands
server=1
#Enable mining
#mining=1
#Enable Staking
#stake=1
#The testnet flag defaults the API port to 7080, RPC to 8336 & mining port to 8325
testnet=1
#To connect to the Nexus public testnet. 
connect=testnet1.nexus-interactions.io
connect=testnet2.nexus-interactions.io
connect=testnet3.nexus-interactions.io
#To disable mainet DNS nodes
nodns=1
#process notifications (incoming transactions) automatically in background
processnotifications=1
#To add a stop password to protect from accidental wallet exit
system/stop=<password>

Ctrl+s & ctrl+x to save and exit the nano text editor. The wallet configuration is now complete.

APIs to Control the Node

To start, stop and check the node info you have to use APIs from the terminal. Change into the LLL-TAO directory to start nexus core (You have to be in the LLL-TAO folder to run all the following commands):

cd LLL-TAO

To start the daemon:

./nexus

Nexus core will be running in the background as a daemon. It will connect to the mining nodes specified in the configuration and synchronize the blockchain. It will take a few minutes to find peers and synchronize the chain.

To stop the daemon:

./nexus system/stop

./nexus system/stop password=<password>

To get the node info:

./nexus system/get/info

Now the testnet node is ready to be used for your application. Hope this guide was helpful!