Bitcoin Core Setup Bash Script

bitcoin.sh

#!/bin/bash

# Bitcoin daemon setup script
# This script sets up bitcoind with proper user, directories, and systemd service

set -e  # Exit on error

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# Function to print colored output
print_status() {
    echo -e "${GREEN}[+]${NC} $1"
}

print_error() {
    echo -e "${RED}[!]${NC} $1"
}

print_warning() {
    echo -e "${YELLOW}[*]${NC} $1"
}

# Check if running as root
if [[ $EUID -ne 0 ]]; then
   print_error "This script must be run as root"
   exit 1
fi

print_status "Starting Bitcoin daemon setup..."

# Check if Bitcoin is installed
if ! command -v bitcoind &> /dev/null; then
    print_error "Bitcoin daemon (bitcoind) is not installed."
    print_warning "Please install Bitcoin Core first. You can download it from:"
    print_warning "https://bitcoin.org/en/download"
    print_warning "Or install via package manager if available for your distribution."
    exit 1
fi

# Create bitcoin user and group if they don't exist
if ! id -u bitcoin &>/dev/null; then
    print_status "Creating bitcoin user and group..."
    useradd -r -s /usr/sbin/nologin -m -d /var/lib/bitcoind bitcoin
else
    print_warning "Bitcoin user already exists"
fi

# Create required directories
print_status "Creating required directories..."

# Configuration directory
mkdir -p /etc/bitcoin
chown root:bitcoin /etc/bitcoin
chmod 710 /etc/bitcoin

# Data directory
mkdir -p /var/lib/bitcoind
chown bitcoin:bitcoin /var/lib/bitcoind
chmod 710 /var/lib/bitcoind

# Runtime directory (will be created by systemd, but we'll set it up)
mkdir -p /run/bitcoind
chown bitcoin:bitcoin /run/bitcoind
chmod 710 /run/bitcoind

# Create basic bitcoin.conf if it doesn't exist
if [ ! -f /etc/bitcoin/bitcoin.conf ]; then
    print_status "Creating basic bitcoin.conf..."
    cat > /etc/bitcoin/bitcoin.conf << 'EOF'
# Bitcoin Core configuration file

# Network-related settings
# Run on the main network (use testnet=1 for testnet)
#testnet=0

# JSON-RPC options (for controlling bitcoind)
server=1
rpcuser=bitcoinrpc
rpcpassword=CHANGE_THIS_PASSWORD_$(openssl rand -hex 32)

# Connection settings
#rpcallowip=127.0.0.1
#rpcport=8332

# Miscellaneous options
txindex=0
prune=550  # Reduce storage requirements to ~550MB (remove this line for full node)

# Performance options
dbcache=450
maxorphantx=10
maxmempool=300
maxconnections=125
maxuploadtarget=1000  # Limit upload to ~1GB per day

# Security
disablewallet=0

# Logging
printtoconsole=0
EOF
    
    # Set proper permissions on config file
    chown root:bitcoin /etc/bitcoin/bitcoin.conf
    chmod 640 /etc/bitcoin/bitcoin.conf
    
    print_warning "Basic bitcoin.conf created. Please edit /etc/bitcoin/bitcoin.conf to:"
    print_warning "  - Change the rpcpassword"
    print_warning "  - Adjust settings according to your needs"
    print_warning "  - Remove 'prune=550' if you want to run a full archival node"
else
    print_warning "bitcoin.conf already exists, skipping creation"
fi

# Create systemd service file
print_status "Creating systemd service file..."
cat > /etc/systemd/system/bitcoind.service << 'EOF'
# It is not recommended to modify this file in-place, because it will
# be overwritten during package upgrades. If you want to add further
# options or overwrite existing ones then use
# $ systemctl edit bitcoind.service
# See "man systemd.service" for details.
# Note that almost all daemon options could be specified in
# /etc/bitcoin/bitcoin.conf, but keep in mind those explicitly
# specified as arguments in ExecStart= will override those in the
# config file.
[Unit]
Description=Bitcoin daemon
Documentation=https://github.com/bitcoin/bitcoin/blob/master/doc/init.md
# https://www.freedesktop.org/wiki/Software/systemd/NetworkTarget/
After=network-online.target
Wants=network-online.target
[Service]
ExecStart=/usr/bin/bitcoind -pid=/run/bitcoind/bitcoind.pid \
                            -conf=/etc/bitcoin/bitcoin.conf \
                            -datadir=/var/lib/bitcoind \
                            -startupnotify='systemd-notify --ready' \
                            -shutdownnotify='systemd-notify --stopping'
# Make sure the config directory is readable by the service user
PermissionsStartOnly=true
ExecStartPre=/bin/chgrp bitcoin /etc/bitcoin
# Process management
####################
Type=notify
NotifyAccess=all
PIDFile=/run/bitcoind/bitcoind.pid
Restart=on-failure
TimeoutStartSec=infinity
TimeoutStopSec=600
# Directory creation and permissions
####################################
# Run as bitcoin:bitcoin
User=bitcoin
Group=bitcoin
# /run/bitcoind
RuntimeDirectory=bitcoind
RuntimeDirectoryMode=0710
# /etc/bitcoin
ConfigurationDirectory=bitcoin
ConfigurationDirectoryMode=0710
# /var/lib/bitcoind
StateDirectory=bitcoind
StateDirectoryMode=0710
# Hardening measures
####################
# Provide a private /tmp and /var/tmp.
PrivateTmp=true
# Mount /usr, /boot/ and /etc read-only for the process.
ProtectSystem=full
# Deny access to /home, /root and /run/user
ProtectHome=true
# Disallow the process and all of its children to gain
# new privileges through execve().
NoNewPrivileges=true
# Use a new /dev namespace only populated with API pseudo devices
# such as /dev/null, /dev/zero and /dev/random.
PrivateDevices=true
# Deny the creation of writable and executable memory mappings.
MemoryDenyWriteExecute=true
# Restrict ABIs to help ensure MemoryDenyWriteExecute is enforced
SystemCallArchitectures=native
[Install]
WantedBy=multi-user.target
EOF

# Reload systemd daemon
print_status "Reloading systemd daemon..."
systemctl daemon-reload

# Enable the service
print_status "Enabling bitcoind service..."
systemctl enable bitcoind.service

# Create a helper script for bitcoin-cli
print_status "Creating bitcoin-cli helper script..."
cat > /usr/local/bin/bitcoin-cli-service << 'EOF'
#!/bin/bash
# Helper script to run bitcoin-cli with correct configuration
exec /usr/bin/bitcoin-cli -conf=/etc/bitcoin/bitcoin.conf "$@"
EOF

chmod +x /usr/local/bin/bitcoin-cli-service

print_status "Setup complete!"
echo ""
print_warning "Important next steps:"
print_warning "1. Edit /etc/bitcoin/bitcoin.conf and change the rpcpassword"
print_warning "2. Review and adjust other settings in bitcoin.conf as needed"
print_warning "3. Start the service with: systemctl start bitcoind"
print_warning "4. Check service status with: systemctl status bitcoind"
print_warning "5. View logs with: journalctl -u bitcoind -f"
print_warning "6. Use bitcoin-cli with: bitcoin-cli-service <command>"
echo ""
print_status "First sync may take several hours to days depending on your configuration."
print_status "If using pruned mode (default in this setup), only ~550MB will be used."