Setting up a Union node on your VPS involves several steps. This guide will walk you through the process, from preparing your system to running the node.

Prerequisites

Before you begin, ensure your VPS meets the following minimum requirements:

• Operating System: Linux-based (Ubuntu recommended)

• CPU: 4 vCPUs or CPU cores

• RAM: More than 8 GB

• Storage: At least 256 GB

These specifications are recommended to ensure optimal performance of your Union node.

STEP 1: UPDATE AND UPGRATE YOUR SYSTEM

Begin by updating your package lists and upgrading existing packages:

sudo apt update && sudo apt full-upgrade -y

sudo apt install build-essential vim jq make git ufw wget -y

STEP 2: SETUP VALIDATOR NAME

Replace YOUR_MONIKER_GOES_HERE with your validator name

MONIKER="YOUR_MONIKER_GOES_HERE"    
   

STEP 3: INSTALL GO (if not installed)

Union testnet requires Go.

Install it with:

cd ~
wget https://go.dev/dl/go1.21.0.linux-amd64.tar.gz
sudo rm -rf /usr/local/go
sudo tar -C /usr/local -xzf go1.21.0.linux-amd64.tar.gz
rm go1.21.0.linux-amd64.tar.gz

Add Go to the system path:

echo "export PATH=$PATH:/usr/local/go/bin" >> ~/.bashrc
source ~/.bashrc

Verify the installation:

go version 

STEP 4: DOWNLOAD BINARIES

# Download project binaries
mkdir -p $HOME/.union/cosmovisor/genesis/bin
wget -O $HOME/.union/cosmovisor/genesis/bin/uniond https://snapshots.kjnodes.com/union-testnet/uniond-v0.25.0-linux-amd64
chmod +x $HOME/.union/cosmovisor/genesis/bin/uniond

# Create application symlinks
ln -s $HOME/.union/cosmovisor/genesis $HOME/.union/cosmovisor/current -f
sudo ln -s $HOME/.union/cosmovisor/current/bin/uniond /usr/local/bin/uniond -f

STEP 5: INSTALL COSMOVISOR AND CREATE A SERVICE

 
# Download and install Cosmovisor
go install cosmossdk.io/tools/cosmovisor/cmd/cosmovisor@v1.6.0

# Create service
sudo tee /etc/systemd/system/union-testnet.service > /dev/null << EOF
[Unit]
Description=union node service
After=network-online.target

[Service]
User=$USER
ExecStart=$(which cosmovisor) run start --home=$HOME/.union
Restart=on-failure
RestartSec=10
LimitNOFILE=65535
Environment="DAEMON_HOME=$HOME/.union"
Environment="DAEMON_NAME=uniond"
Environment="UNSAFE_SKIP_BACKUP=true"
Environment="PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:$HOME/.union/cosmovisor/current/bin"

[Install]
WantedBy=multi-user.target
EOF
sudo systemctl daemon-reload
sudo systemctl enable union-testnet.service

STEP 6: INITIALIZE THE NODE

# Workaround mandatory home argument
alias uniond='uniond --home=$HOME/.union/'

# Set node configuration
uniond config set client chain-id union-testnet-9
uniond config set client keyring-backend test
uniond config set client node tcp://localhost:17157

# Initialize the node
uniond init $MONIKER --chain-id union-testnet-9 --home=$HOME/.union

# Download genesis and addrbook
curl -Ls https://snapshots.kjnodes.com/union-testnet/genesis.json > $HOME/.union/config/genesis.json
curl -Ls https://snapshots.kjnodes.com/union-testnet/addrbook.json > $HOME/.union/config/addrbook.json

# Add seeds
sed -i -e "s|^seeds *=.*|seeds = \"3f472746f46493309650e5a033076689996c8881@union-testnet.rpc.kjnodes.com:17159\"|" $HOME/.union/config/config.toml

# Set minimum gas price
sed -i -e "s|^minimum-gas-prices *=.*|minimum-gas-prices = \"0muno\"|" $HOME/.union/config/app.toml

# Set pruning
sed -i \
  -e 's|^pruning *=.*|pruning = "custom"|' \
  -e 's|^pruning-keep-recent *=.*|pruning-keep-recent = "100"|' \
  -e 's|^pruning-keep-every *=.*|pruning-keep-every = "0"|' \
  -e 's|^pruning-interval *=.*|pruning-interval = "19"|' \
  $HOME/.union/config/app.toml

# Set custom ports
sed -i -e "s%^proxy_app = \"tcp://127.0.0.1:26658\"%proxy_app = \"tcp://127.0.0.1:17158\"%; s%^laddr = \"tcp://127.0.0.1:26657\"%laddr = \"tcp://127.0.0.1:17157\"%; s%^pprof_laddr = \"localhost:6060\"%pprof_laddr = \"localhost:17160\"%; s%^laddr = \"tcp://0.0.0.0:26656\"%laddr = \"tcp://0.0.0.0:17156\"%; s%^prometheus_listen_addr = \":26660\"%prometheus_listen_addr = \":17166\"%" $HOME/.union/config/config.toml
sed -i -e "s%^address = \"tcp://0.0.0.0:1317\"%address = \"tcp://0.0.0.0:17117\"%; s%^address = \":8080\"%address = \":17180\"%; s%^address = \"0.0.0.0:9090\"%address = \"0.0.0.0:17190\"%; s%^address = \"0.0.0.0:9091\"%address = \"0.0.0.0:17191\"%; s%:8545%:17145%; s%:8546%:17146%; s%:6065%:17165%" $HOME/.union/config/app.toml

STEP 6: DOWNLOAD CHAIN’S LATEST SNAPSHOT

 
curl -L https://snapshots.kjnodes.com/union-testnet/snapshot_latest.tar.lz4 | tar -Ilz4 -xf - -C $HOME/.union
[[ -f $HOME/.union/data/upgrade-info.json ]] && cp $HOME/.union/data/upgrade-info.json $HOME/.union/cosmovisor/genesis/upgrade-info.json

STEP 7: START SERVICE AND CHECK THE LOGS

sudo systemctl start union-testnet.service && sudo journalctl -u union-testnet.service -f --no-hostname -o cat

Common Troubleshooting

1. Snapshot Extraction Fails (lz4 Error)

Error Message
"tar (grandchild): lz4: Cannot exec: No such file or directory"

Fix: Install lz4 manually:

sudo apt install lz4 -y

Then retry snapshot extraction.