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

[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):

[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):

[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