Setting up Nebula Sync for two Pi-hole instances (worksheet)

THE TUTORIAL IS MEANT TO BE USED WITH THIS VIDEO!

YouTube tutorials can be a pain to actually follow, so here’s the worksheet that accompanies the video - for your convenience.

I recommend both printing this out, to use as a checklist, and keeping the page up, so you can copy-and-paste the entries.

What you need:

1. 2 instances of Pi-hole

2. SSH access to both Pi-holes

3. Pi-hole web UI passwords for both Pi-hole instances

STEP 1: Designate Primary and Secondary Pi-hole Instances

1. Record hostname and IP of your primary Pi-hole here:

   _____________/_____________

2. Record hostname and IP of your secondary Pi-hole here:

   _____________/_____________

STEP 2: Prepare Secondary Pi-hole

Connect to your secondary Pi-hole instance via SSH:

open a terminal window on your Windows computer, WIN + R > cmd > Enter

[copy/paste >] ssh USERNAME@IP_ADDRESS_OF_RPi  

(for example: ssh netserv@192.168.0.11)

Enter password from step 1, #6 of the primary Pi-hole’s worksheet

[copy/paste >] sudo pihole-FTL --config webserver.api.app_sudo true

[copy/paste >] sudo systemctl restart pihole-FTL

STEP 3: Download and Install Nebula Sync

Connect to your primary Pi-hole instance via SSH:

[copy/paste >] cd /tmp

The rest of the lines in this step need to be modified if you are not using an arm64 device (like a Raspberry Pi 3, Zero 2, or higher). Depending on the CPU architecture, you’ll need to change it something like amd64, armv7m, or rv64gc. This will affect the curl, tar, and rm steps.

[copy/paste >] URL=$(curl -s https://api.github.com/repos/lovelaze/nebula-sync/releases/latest | grep "browser_download_url.*linux_arm64.tar.gz" | cut -d '"' -f 4)

[copy/paste >] wget $URL

[copy/paste >] tar -xvf nebula-sync_*_linux_arm64.tar.gz

[copy/paste >] sudo mv nebula-sync /usr/local/bin/

[copy/paste >] sudo chmod +x /usr/local/bin/nebula-sync

[copy/paste >] rm nebula-sync_*_linux_arm64.tar.gz

STEP 4: Create Nebula Sync Config

(still in SSH on the primary Pi-hole):

Replace netserv with the username that you use to connect via SSH!

[copy/paste >] mkdir -p /home/netserv/.config/nebula-sync

[copy/paste >] nano /home/netserv/.config/nebula-sync/nebula.env

copy from here>

PRIMARY=http://192.168.0.11|pihole
REPLICAS=http://192.168.0.12|pihole
FULL_SYNC=true
RUN_GRAVITY=true

 <to here, and paste it into nano

Note: changing the IP addresses of your primary and secondary instances, and changing the passwords to what you had at the end of Step 4 on the original Pi-hole setup worksheets.  If you copy and pasted the setpassword line as-is, your passwords may also be set to “pihole” 

Exit (Control-X) and Save (yes)

STEP 5: Create the Service File

(still in SSH on the primary Pi-hole):

[copy/paste >] sudo nano /etc/systemd/system/nebula-sync.service

copy from here>

[Unit]
Description=Nebula Sync Service
After=network.target

[Service]
Type=oneshot
User=netserv
ExecStart=/usr/local/bin/nebula-sync run --env-file /home/netserv/.config/nebula-sync/nebula.env

 <to here, and paste it into nano

Note: change the user from netserv to what you had at Step 1 #6 on the original Pi-hole setup worksheet 

Exit (Control-X) and Save (yes)

STEP 6: Create the Timer File

(still in SSH on the primary Pi-hole):

[copy/paste >] sudo nano /etc/systemd/system/nebula-sync.timer

copy from here>

[Unit]
Description=Run Nebula Sync every 15 minutes

[Timer]
OnBootSec=2min
OnUnitActiveSec=15min

[Install]
WantedBy=timers.target

 <to here, and paste it into nano

Exit (Control-X) and Save (yes)

[copy/paste >] sudo systemctl daemon-reload

[copy/paste >] sudo systemctl enable --now nebula-sync.timer

STEP 7: Manual Test

(still in SSH on the primary Pi-hole):

Replace netserv with the username that you use to connect via SSH!

[copy/paste >] sudo -u netserv /usr/local/bin/nebula-sync run --env-file /home/netserv/.config/nebula-sync/nebula.env

NOTE: If you have any issues, please comment on the original video for assistance