Set Up Apache Virtual Hosts on Ubuntu 20.04

Tip: Ubuntu 20.04 is an older release. Newer Ubuntu versions use the same steps.

What is a virtual host?

Apache is a web server program. A virtual host is a set of rules for one website. It lets one server serve many sites, like one apartment block with many flats. Each flat has its own name on the door.

Steps

Install Apache:

sudo apt update
sudo apt install apache2 -y

Create a folder for your site's files:

sudo mkdir -p /var/www/example.com/public_html

Give your user ownership of it:

sudo chown -R $USER:$USER /var/www/example.com/public_html
sudo chmod -R 755 /var/www/example.com

Create a test page:
```
nano /var/www/example.com/public_html/index.html
```
Type a short line such as <h1>Welcome to example.com</h1>. Press Ctrl+O, then Enter to save, and Ctrl+X to leave.

Create the virtual host file:

sudo nano /etc/apache2/sites-available/example.com.conf

Put this inside it:

<VirtualHost *:80>
    ServerAdmin webmaster@example.com
    ServerName example.com
    ServerAlias www.example.com
    DocumentRoot /var/www/example.com/public_html
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>

Change example.com to your own domain.

Turn on your new site:
```
sudo a2ensite example.com.conf
```
Turn off the default Apache site, if you do not need it:
```
sudo a2dissite 000-default.conf
```
Check for mistakes:
```
sudo apache2ctl configtest
```
You should see "Syntax OK".
Restart Apache:
```
sudo systemctl restart apache2
```
If the firewall UFW is on, allow web traffic:
```
sudo ufw allow 'Apache Full'
```
Point your domain's A record to the server IP. An A record links a domain name to a number address. Then open your domain in a browser.

For a second website, repeat steps 3 to 11 with another domain name and folder.

Tip: Add free HTTPS later with Certbot. It adds a second virtual host for port 443 for you.

Warning: the command a2dissite removes a site from the active list. Check which site you are turning off, so you do not take a live site offline.

Quick recap

A virtual host lets one server show many sites.
Make a folder and a .conf file for each site.
Use a2ensite to switch it on.
Run apache2ctl configtest, then restart Apache.
Point the domain to your server.