Dev:Run a Private Node

This guide will help to set up a private testnet. The Nexus wallet is used to run public, private and hybrid networks, the configuration is what sets them apart. The private and hybrid networks will not be compatible with legacy.

In a private network, throughput can be increased by adding additional nodes and that can be done at a later stage. In a private network there is no mining or staking needed to secure the network.

This guide is based on ubuntu server 20.04 LTS, use any distribution of your choice. I am using raspbian 64-bit on a Raspberry Pi 4.

Prerequisites

• Ubuntu server 20.04 LTS for AMD/IA64 or Ubuntu IOT for Raspberry Pi. (Use any linux distribution of choice, but this guide is tailored for 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.

Ubuntu IOT default login credentials:

username=ubuntu
password=ubuntu

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 and upgrade your node:

sudo apt update; sudo apt upgrade -y

Open SSH port 22 before you enable the firewall:

sudo ufw allow ssh

Enable firewall:

sudo ufw enable

Check firewall status:

sudo ufw status

Set 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

Reboot node:

sudo reboot

Now the computer is ready to install the nexus core.

Compile The Core

Install the dependencies required for compiling nexus core, It will take some time to complete depending on your internet speed:

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

Download the latest nexus core 5.1 source code, should only take a few seconds to complete (This link may change as development progresses):

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

Change into the source code directory:

cd LLL-TAO

Run the command to compile from source, please be patient, as this can take a very long time depending on your CPU. Replace the 1 in ‘j1’ to the number of cores / threads for compiling faster:

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

For compiling on Raspberry Pi, use:

make -f makefile.cli -j1 ARM64=1 NO_WALLET=1

The output show the message “Finished building nexus” on a successful compile. The make command creates a new executable file named 'nexus'. To check use the command:

ls

There are two ways to access the wallet; from the LLL-TAO folder, API's can be accessed from this location only via terminal and for every command you have to specify the path (./) before the executable filename (./nexus) or if the executable file is moved to the /usr/bin directory, it can be accessed universally from any location without path (nexus). For this guide will not use the path.

To move the nexus executable to the /usr/bin folder:

sudo mv ˜ /LLL-TAO/nexus /usr/bin

Configure the Core

Create Nexus core directory (it’s a hidden directory, Nexus daemon creates it automatically on first start. We are creating it manually to create the configuration file. If you have the directory you can skip this step):

mkdir ~/.Nexus

Create the nexus.conf file:

nano ~/.Nexus/nexus.conf

Copy the code below, to the nexus.conf file with ctrl+shift+v and edit or disable the parameters as per your needs:

 #Nexus private standalone node config- Only for 5.1 rc1 & above
 #
 #Default API user/pass to blank for private network
 #apiuser=<username>
 #apipassword=<password>
 #Disable authentication of API requests
 apiauth=0
 #To remotely access the node API's
 apiremote=1
 #Change API port to 7080 (API port in private mode defaults to 7080, RPC defaults to 8336)
 #apiport=7080
 #To remotely access API's use the llpallowip flag.
 #The <ipaddress> can use wildcards; (llpallowip=192.168.*.*:7080)
 llpallowip=<ipaddress>:7080
 #Run wallet as a daemon
 daemon=1
 #Run node in private mode (defaults to testnet in 5.1)
 private=1
 #Run as a standalone node. (Disable this on additional nodes)
 manager=0
 #Run as a local node, disable for public node
 nodns=1
 #Enables multiple users to be logged in concurrently
 multiuser=1
 #Latency is in ms, this is the min time between blocks
 latency=500
 #Enables creation of blocks in private mode.( Use only on one node) (Use a secure password)
 generate=<password>
 #To connect additional nodes use addnode flag, the ipaddress will be of the first node with the ‘generate’ flag)
 addnode=<ipaddress>
 #To avoid accidental node shutdown with the stop command
 system/stop=<password>

Ctrl+s and Ctrl+x to save and exit the editor.

Note: To add an additional node to the private network, disable ‘manager’ and ‘generate’ flags. Add the ‘addnode’ flag with ipaddress referring to the first node or the one with the ‘generate’ flag and an additional line for any other node in the network.

Nexus API Commands

To interact with the nexus core, use API commands via the terminal or remotely.

If you have any doubts you can refer to the API documentation here. The documentation for 5.1.rc1 may take some time to be updated at the time of writing the guide.

Open port 7080 and 8336 on the firewall:

 sudo ufw allow 7080/tcp
 sudo ufw allow 8336/tcp

If the executable is in the LLL-TAO directory to start nexus core, change into the LLL-TAO folder to run all the following commands:

 cd LLL-TAO

To start the daemon, use the path and the executable file name:

 ./nexus

If you have moved the nexus executable file to the /user/bin then use the following command from any location:

 nexus

Nexus core will be running in the background as a daemon. It will detect peers, if available and synchronize the blockchain. To stop the daemon without password protection in config:

 nexus system/stop

To stop the daemon with password protection in config:

 nexus system/stop password=<password>

To get your node info:

 nexus system/get/info

To monitor your logs:

 tail -f ~/.Nexus/testnet1/log/0.log

Username must be a minimum of 2 characters, passwords must be 8 characters and pin 4 characters. The PIN can be a combination of letters/numbers/symbols. To create a user account (signature chain):

 nexus users/create/user username=<username> password=<password> pin=<pin>

Multiuser mode creates a new session for every user when they log in and that session ID will be used for unlocking and other user API's. Save this session ID for future use and it will be active till the user logs out. To log into your account:

 nexus users/login/user username=<username> password=<password> pin=<pin>

To unlock the account for automatically credit incoming transactions set (notifications=1). If it's not set you will have to manually credit the incoming transactions else it will be credited to the sender's account after 24 hrs. This is the reversible transaction function working as designed.

 nexus users/unlock/user pin=<pin> notifications=1 session=<sessionid>

To check the full node metrics:

 nexus system/get/metrics

The API commands can be used from the browser and output in JSON is displayed (JSON formatter extension used to parse the JSON output).