function get_client_mac_address() {
  # Usage: get_client_mac_address <interface_name>
  local ETH_IFACE="$1"
  local TARGET_IP="192.168.2.2"

  # Check if the interface is plugged in
  if ip link show "$ETH_IFACE" | grep -q "state UP"; then
    local MAC_ADDRESS=$(arp -i "$ETH_IFACE" -n | grep "$TARGET_IP" | awk '{print $3}')

    if [ -n "$MAC_ADDRESS" ]; then
      echo "$MAC_ADDRESS"
    else
      exit 1
    fi
  else
    exit 1
  fi
}