Step-by-step guide to set up a local Monero node on a Raspberry Pi 3

Monero node on a Raspberry Pi Note Certain steps assume macOS as your primary operating system. Hardware microSD card Download the compressed “Ubuntu MATE 16.04.2 (Xenial)” image for Raspberry Pi ubuntu-mate-16.04.2-desktop-armhf-raspberry-pi.img.xz from https://ubuntu-mate.org/download/. Verify the checksum: $ shasum -a 256 ubuntu-mate-16.04.2-desktop-armhf-raspberry-pi.img.xz Uncompress it with gunzip: $ gunzip ubuntu-mate-16.04.2-desktop-armhf-raspberry-pi.img.xz Alternatively, use xz -d or The Unarchiver. Insert the microSD card via a USB adapter into the computer. Identify the correct device of the microSD card with the diskutil list command, e.g. /dev/disk3: $ diskutil list … /dev/disk3 (external, physical): #: TYPE NAME SIZE IDENTIFIER 0: FDisk_partition_scheme *128.0 GB disk3 1: Windows_NTFS SS 128.0 GB disk3s1 Unmount the existing file system, e.g. /dev/disk3s1: $ sudo diskutil unmount /dev/disk3s1 Transfer the OS image to the microSD card, e.g. /dev/rdisk3: $ sudo dd if=ubuntu-mate-16.04.2-desktop-armhf-raspberry-pi.img of=/dev/rdisk3 bs=1m On the desktop, you'll see a device labeled PI_BOOT. Unmount it and remove the USB adapter from the computer. Ubuntu MATE Insert the microSD card into the Raspberry Pi, and attach both the HDMI cable and the USB keyboard (and mouse) before connecting the power cord. Complete the “System Configuraton” dialog sections. For this tutorial, I chose these values at the “Who are you?” section: Your computer's name: computer Pick a username: username Installation will automatically start upon completion. Next, log in and open a terminal (Applications → System Tools → MATE Terminal). You'll see a prompt like this: username@computer:~$ However, for simplicity of this tutorial, I'll just display the prompt like this: $ Wireless Display the Raspberry Pi's MAC address: $ ifconfig wlan0 | head -1 wlan0 Link encap:Ethernet Hwaddr **:**:**:**:**:** Add this address to the exception list of your wireless router's MAC address filter. Edit /etc/network/interfaces and add the following section, e.g. using 192.168.0.100 as IP address and 192.168.0.1 as default gateway: $ sudo vi /etc/network/interfaces # Wireless auto wlan0 # iface wlan0 inet dhcp iface wlan0 inet static address 192.168.0.100 netmask 255.255.255.0 gateway 192.168.0.1 wpa-conf /etc/wpa_supplicant.conf dns-nameservers 8.8.8.8 8.8.4.4 Note: Comment out address, netmask, gateway and dns-nameservers if you prefer to use dhcp instead of static. The DNS servers 8.8.8.8 and 8.8.4.4 are those of Google, obviously feel free to replace them. Create the file /etc/wpa_supplicant.conf, which contains the wireless network details. Replace ADD-YOUR-SSID-HERE and ADD-YOUR-WPA-PASSWORD-HERE with the actual values: $ sudo vi /etc/wpa_supplicant.conf network={ ssid="ADD-YOUR-SSID-HERE" proto=RSN key_mgmt=WPA-PSK pairwise=CCMP TKIP group=CCMP TKIP psk="ADD-YOUR-WPA-PASSWORD-HERE" } Change the permissions of the above file to 640: $ sudo chmod o-r /etc/wpa_supplicant.conf Stop the current instance of the service apt-daily.service that is likely still running: $ sudo systemctl stop apt-daily.service Install the SSH package, and enable the service: $ sudo apt-get install openssh-server $ sudo systemctl enable ssh Finally, restart the Raspberry Pi, and log in remotely from macOS to verify: $ ssh [email protected] [email protected]'s password: ******** Welcome to Ubuntu 16.04.2 LTS (GNU/Linux 4.4.38-v7+ armv7l) … VNC Next, proceed with installing the x11vnc package: $ sudo apt-get install x11vnc Create an x11vnc password file in /etc: $ sudo x11vnc -storepasswd t0ps3cr3t /etc/x11vnc.password Interactively start up the VNC server: $ sudo x11vnc -shared -no6 -forever -nolookup -auth guess -rfbauth /etc/x11vnc.password Connect to the Raspberry Pi using a VNC client, e.g. the macOS Screen Sharing application. If it works, press Control + C in the Raspberry Pi terminal to stop the x11vnc process. Next, create a service for x11vnc: $ sudo vi /lib/systemd/system/x11vnc.service Add the following contents: [Unit] Description="VNC Server for X11" Requires=display-manager.service After=display-manager.service [Service] ExecStart=/usr/bin/x11vnc -shared -no6 -forever -nolookup -auth guess -rfbauth /etc/x11vnc.password ExecStop=/usr/bin/killall x11vnc Restart=on-failure Restart-sec=2 [Install] WantedBy=multi-user.target And ensure the service starts on boot: $ sudo systemctl enable x11vnc Next, configure a display size of 1200 × 800 when running headless: $ sudo crontab -e Select an editor, e.g. type 3 if you prefer vim. Add the following entry: @reboot /bin/fbset -g 1280 800 1280 800 24 Note: The above fbset command must run before X is started. Hence the @reboot entry. Disable X logging by editing /etc/X11/Xsession: $ sudo vi /etc/X11/Xsession Search for exec >>"$ERRFILE" 2>&1, and make the following change: < exec >>"$ERRFILE" 2>&1 --- > # exec >>"$ERRFILE" 2>&1 > exec >> /dev/null 2>&1 Restart the Raspberry Pi, and verify that SSH and VNC still work. Then finally, shutdown the Raspberry Pi. Disconnect both the HDMI cable and USB keyboard (and mouse), and restart the Raspberry Pi headless, i.e. with only the power cord attached to the device. Test SSH and VNC again. File Systems Note: Since Ubuntu MATE 16.04.2 (Xenial) automatically resizes the root partition / upon installation, once booted, we can't simply resize it anymore. Therefore, you'll either have to use another Linux computer to perform the following operation, or repeat the above steps using a spare microSD card. Either way, insert the high-performance microSD card via a USB adapter into the temporary Linux computer. There, first install the graphical GParted utility if necessary: $ sudo apt-get install gparted Start the GParted utility via: System → Administration → GParted. Select the device that corresponds with the high-performance microSD card, in this case /dev/sda: Select the root partition / and choose Partition → Resize/Move from the menu: Specify 8192 MiB as the new size, and click “Resize/Move”: Then, add a 3rd primary partition: File System: linux-swap Label: SWAP Size: 1024 MiB Next, add a 4rd primary partition: File System: ext4 Label: SPACE Size: remaining unallocated There should now be 3 pending operations: Apply the changes, and confirm: After a while, they are applied: The disk layout for /dev/sda should now look like this: Eject the high-performance microSD card, and insert it back into the Raspberry Pi. There, create the /Space mount point: $ sudo mkdir /Space $ sudo chmod 755 /Space Edit the file /etc/fstab with sudo vi /etc/fstab, and add the last 2 lines for the swap and /Space mount points: proc /proc proc defaults 0 0 /dev/mmcblk0p2 / ext4 defaults,noatime 0 1 /dev/mmcblk0p1 /boot/ vfat defaults 0 2 /dev/mmcblk0p3 swap swap defaults 0 0 /dev/mmcblk0p4 /Space ext4 defaults,noatime 0 0 Important: The noatime mount option is very important as without it, every single file access on the file system would perform a write operation to the microSD card. Finally, restart the sytem: $ sudo reboot Verify the /Space file system with the df utility: $ df -h /Space Filesystem Size Used Avail Use% Mounted on /dev/mmcblk0p4 109G 60M 103G 1% /Space Memory and Swap Display the Raspberry Pi's memory and swap comsumption: $ free total used free shared buff/cache available Mem: 947732 72372 690540 20796 184820 799956 Swap: 1048572 0 1048572 Display the “swappiness” value: $ cat /proc/sys/vm/swappiness 60 The swappiness parameter controls the tendency of the kernel to move processes out of physical memory and onto the swap disk. Change the value to 0 to avoid using swap space as much as possible: $ sudo sysctl vm.swappiness=0 Make it permanent: $ sudo vi /etc/sysctl.conf And add the following line to that file: vm.swappiness = 0 Software Update Perform a software update: $ sudo apt-get update $ sudo apt-get upgrade $ sudo rpi-update $ sudo reboot Also, install the Chromium web browser: $ sudo apt-get install chromium-browser Monero Start the Chromium web browser and download the latest Monero release for ARMv7, e.g. monero-linux-armv7-v0.11.1.0.tar.bz2, from https://downloads.getmonero.org/cli/linuxarm7. Create a directory for the Monero software, and install the downloaded software in /opt: $ sudo su - # cd /opt # mkdir monero-linux-armv7-v0.11.1.0 # ln -s ${_} monero # cd monero # bzcat /home/username/Downloads/monero-linux-armv7-v0.11.1.0.tar.bz2 | tar -xf - # exit Create a non-privileged monero user: $ sudo adduser monero Specify a password and provide Monero as “Full Name”. Create a directory underneath /Space for the monero user: $ sudo su - # cd /Space # mkdir monero # sudo chown monero:monero # exit Create the physical location for the Monero blockchain under /Space/monero to avoid having to use monerod's --data-dir parameter: $ sudo su - monero $ ln -s /Space/monero Space $ mkdir Space/bitmonero $ ln -s Space/bitmonero .bitmonero Optionally, add the Monero software path to your own PATH variable by editing the .profile file if you intend to use the monero-wallet-cli from the Raspberry Pi later on: # Monero PATH="${PATH}:/opt/monero" Create a service for the Monero daemon with sudo vi /lib/systemd/system/monerod.service, and add the following contents: [Unit] Description=Monero's distributed currency daemon After=network.target [Service] User=monero Group=monero Type=forking ExecStart=/opt/monero/monerod --restricted-rpc --rpc-bind-ip 192.168.0.100 --confirm-external-bind --fluffy-blocks --block-sync-size 1 --detach KillMode=process Restart=on-failure TimeoutSec=120 [Install] WantedBy=multi-user.target Disable services that aren't strictly necessary, to save memory going forward, and then restart the Raspberry Pi: $ for SERVICE in x11vnc bluetooth cups; do sudo systemctl disable ${SERVICE}; done $ sudo reboot Transfer a fully synchronized .bitmonero blockchain folder from macOS to the Raspberry Pi into the directory /home/monero/.bitmonero to speed up the synchronization process, e.g. via a USB-stick. Make sure the files are owned by the monero user: $ sudo chown -R monero:monero /home/monero/.bitmonero As the monero user, manually start the monerod daemon interactively, thus without the --detach parameter to verify whether it functions correctly: $ sudo su - monero $ /opt/monero/monerod --restricted-rpc --rpc-bind-ip 192.168.0.100 --confirm-external-bind --fluffy-blocks --block-sync-size 1 … Wait until it prints SYNCHRONIZED OK. Then, type exit to stop the daemon, and once again to return to your own user: $ exit You're now ready to enable the monerod service, and restart the system for the last time: $ sudo systemctl enable monerod $ sudo reboot You can now use the IP address of your Raspberry Pi as a local node, with port number 18081. That's it! 🍺