Change apache Document Root on Linux

 

Introduction

On Ubuntu, the Apache web server stores its documents in /var/www/html, which is typically located on the root filesystem with rest of the operating system. Sometimes, though, it’s helpful to move the document root to another location, such as a separate mounted filesystem. For example, if you serve multiple websites from the same Apache instance, putting each site's document root on its own volume allows you to scale in response to the needs of a specific site or client.
In this guide, you will move an Apache document root to a new location.

Prerequisites

To complete this guide, you will need:

• An Ubuntu 18.04 server and a non-root user with sudo privileges. You can learn more about how to set up a user with these privileges in our Initial Server Setup with Ubuntu 18.04 guide.
• Apache installed, following How To Install the Apache Web Server on Ubuntu 18.04.
• SSL configured for your domain following How To Secure Apache with Let's Encrypt on Ubuntu 18.04. We will use the domain name example.com in this tutorial, but you should substitute this with your own domain name.
• A new location for your document root. In this tutorial, we will use the /mnt/volume-nyc3-01 directory for our new location. If you are using Block Storage on DigitalOcean, this guide will show you how to create and attach your volume. Your new document root location is configurable based on your needs, however. If you are moving your document root to a different storage device, you will want to select a location under the device's mount point.

Step 1 — Copying Files to the New Location

On a fresh installation of Apache, the document root is located at /var/www/html. By following the prerequisite guides, however, you created a new document root, /var/www/example.com/html. You may also have additional document roots in corresponding VirtualHost directives. In this step, we will establish the location of our document roots and copy the relevant files to their new location.
You can search for the location of your document roots using grep. Let's search in the /etc/apache2/sites-enabled directory to limit our focus to active sites. The -R flag ensures that grep will print both the DocumentRoot and the full filename in its output:

grep -R "DocumentRoot" /etc/apache2/sites-enabled

If you followed the prerequisite tutorials on a fresh server, the result will look like this:

Output
/etc/apache2/sites-enabled/example.com-le-ssl.conf:  DocumentRoot /var/www/example.com/html
/etc/apache2/sites-enabled/example.com.conf:         DocumentRoot /var/www/example.com/html

If you have pre-existing setups, your results may differ from what's shown here. In either case, you can use the feedback from grep to make sure you’re moving the desired files and updating the appropriate configuration files.
Now that you've confirmed the location of your document root, you can copy the files to their new location with rsync. Using the -a flag preserves the permissions and other directory properties, while -v provides verbose output so you can follow the progress of the sync:
Note: Be sure there is no trailing slash on the directory, which may be added if you use tab completion. When there’s a trailing slash, rsync will dump the contents of the directory into the mount point instead of transferring it into a containing html directory.

sudo rsync -av /var/www/example.com/html /mnt/volume-nyc3-01

You will see output like the following:

Output
sending incremental file list
html/
html/index.html

sent 318 bytes  received 39 bytes  714.00 bytes/sec
total size is 176  speedup is 0.49

With our files in place, let's move on to modifying our Apache configuration to reflect these changes.

Step 2 — Updating the Configuration Files

Apache makes use of both global and site-specific configuration files. For background about the hierarchy of configuration files, take a look at How To Configure the Apache Web Server on an Ubuntu or Debian VPS. We will modify the virtual host files for our example.com project: /etc/apache2/sites-enabled/example.com.conf and /etc/apache2/sites-enabled/example.com-le-ssl.conf, which was created when we configured SSL certificates for example.com.
Note: Remember that in your case example.com will be your_domain_name, and that you will be modifying the virtual host files that were outputted when you ran the grep command in Step 1.
Start by opening /etc/apache2/sites-enabled/example.com.conf:

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

Find the line that begins with DocumentRoot and update it with the new root location. In our case this will be /mnt/volume-nyc3-01/html:

/etc/apache2/sites-enabled/example.com.conf

<VirtualHost *:80>
    ServerAdmin sammy@example.comn
    ServerName example.com
    ServerAlias www.example.com
    DocumentRoot /mnt/volume-nyc3-01/html
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
RewriteEngine on
RewriteCond %{SERVER_NAME} =www.example.com [OR]
RewriteCond %{SERVER_NAME} =example.com
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
</VirtualHost>

Let's also add directives to ensure that the server will follow the symbolic links in the directory:

/etc/apache2/sites-enabled/example.com.conf

. . .
<Directory /mnt/volume-nyc3-01/html>
    Options FollowSymLinks
    AllowOverride None
    Require all granted
</Directory>

Keep an eye out for the DocumentRoot that grep outputted in Step 1, including in aliases or rewrites. You will also want to update these to reflect the new document root location.
After saving these changes, let's turn our attention to the SSL configuration. Open /etc/apache2/sites-enabled/example.com-le-ssl.conf:

sudo nano /etc/apache2/sites-enabled/example.com-le-ssl.conf

Modify the DocumentRoot to reflect the new location, /mnt/volume-nyc3-01/html:

/etc/apache2/sites-enabled/example.com-le-ssl.conf

<IfModule mod_ssl.c>
<VirtualHost *:443>
    ServerAdmin sammy@example.com
    ServerName example.com
    ServerAlias www.example.com
    DocumentRoot /mnt/volume-nyc3-01/html
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
. . .
</VirtualHost>
</IfModule>

You have now made the necessary configuration changes to reflect the new location of your document root.

Step 3 — Restarting Apache

Once you’ve finished making the configuration changes, you can restart Apache and test the results.
First, make sure the syntax is right with configtest:

 sudo apachectl configtest

On a fresh installation you will get feedback that looks like this:

Output
AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
Syntax OK

If you want to suppress the top line, just add a ServerName directive to your main (global) Apache configuration file at /etc/apache2/apache2.conf. The ServerName can be your server's domain or IP address. This is just a message, however, and doesn't affect the functionality of your site. As long as the output contains Syntax OK, you are ready to continue.
Use the following command to restart Apache:

sudo systemctl reload apache2

When the server has restarted, visit your affected sites and ensure that they’re working as expected. Once you’re comfortable that everything is in order, don’t forget to remove the original copies of the data:

sudo rm -Rf /var/www/example.com/html

You have now successfully moved your Apache document root to a new location.

Conclusion

In this tutorial, we covered how to change the Apache document root to a new location. This can help you with basic web server administration, like effectively hosting multiple sites on a single server. It also allows you to take advantage of alternative storage devices such as network block storage, which can be helpful in scaling a web site as its needs change.