Wireguard and Nextcloud server at home

To achieve this, follow these steps:

Set up the NextCloud Server on the First Raspberry Pi (RPi1):

Install the required packages:

sudo apt update
sudo apt upgrade
sudo apt install apache2 mariadb-server libapache2-mod-php7.3
sudo apt install php7.3-gd php7.3-json php7.3-mysql php7.3-curl php7.3-mbstring
sudo apt install php7.3-intl php-imagick php7.3-xml php7.3-zip

Now download and install NextCloud:

cd /var/www/html/
sudo wget https://download.nextcloud.com/server/releases/nextcloud-22.0.0.zip
sudo unzip nextcloud-22.0.0.zip
sudo chown -R www-data:www-data nextcloud
sudo chmod 755 -R nextcloud

Create a new database for NextCloud:

sudo mariadb
CREATE DATABASE nextcloud;
CREATE USER 'nextcloud'@'localhost' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON nextcloud.* TO 'nextcloud'@'localhost';
FLUSH PRIVILEGES;
QUIT;

Now, configure the Apache server to work with NextCloud:

sudo nano /etc/apache2/sites-available/nextcloud.conf

Paste the following:

Alias /nextcloud "/var/www/html/nextcloud/"
<Directory /var/www/html/nextcloud/>
Require all granted
AllowOverride All
Options FollowSymLinks MultiViews
<IfModule mod_dav.c>
Dav off
</IfModule>
SetEnv HOME /var/www/html/nextcloud
SetEnv HTTP_HOME /var/www/html/nextcloud
</Directory>

Enable the site, rewrite module, and restart Apache:

sudo a2ensite nextcloud.conf
sudo a2enmod rewrite
sudo systemctl restart apache2

Set up WireGuard on Both Raspberry Pis (RPi1 & RPi2):

WireGuard setup involves generating public and private keys on both servers, and then exchanging these keys between the servers.

On each Pi, install WireGuard:

sudo apt install wireguard

Generate the public and private keys:

umask 077
wg genkey > privatekey
wg pubkey < privatekey > publickey

On RPi1, configure WireGuard:

sudo nano /etc/wireguard/wg0.conf

Add the following configuration, replacing the placeholders with your values:

[Interface]
Address = 10.0.0.1/24
SaveConfig = true
PrivateKey = RPi1_PRIVATE_KEY
ListenPort = 51820

[Peer]
PublicKey = RPi2_PUBLIC_KEY
AllowedIPs = 10.0.0.2/32

On RPi2, configure WireGuard:

sudo nano /etc/wireguard/wg0.conf

Add the following configuration, replacing the placeholders with your values:

[Interface]
Address = 10.0.0.2/24
SaveConfig = true
PrivateKey = RPi2_PRIVATE_KEY
ListenPort = 51820

[Peer]
PublicKey = RPi1_PUBLIC_KEY
AllowedIPs = 10.0.0.1/32
Endpoint = RPi1_PUBLIC_IP:51820

Start and enable WireGuard on both Pis:

sudo systemctl start wg-quick@wg0
sudo systemctl enable wg-quick@wg0

Set Up Rsync for Backups:

Install rsync on both Pis:
```
sudo apt-get install rsync
```
On RPi1, set up SSH keys for passwordless login:
```
ssh-keygen -t rsa
ssh-copy-id username@RPi2
```
Now create a cronjob to perform the backup. Open the crontab editor:
```
crontab -e
```
Add a new line to your crontab that calls rsync:
```
0 2 * * * rsync -az /path/to/nextcloud/data username@RPi2:/path/to/backup/location
```
This will perform a backup of the NextCloud data folder from RPi1 to RPi2 every day at 2 AM.

This provides a basic setup for a geodiverse backup strategy for NextCloud using WireGuard for secure connections and rsync for data transfer. You might need to further adjust configurations to suit your particular needs, for example by hardening server security, optimizing performance, or handling exceptions during data transfer.