Title: Subdomain and subdirectory structures
Author: WordPress VIP Documentation
Published: September 17, 2020
Last modified: August 8, 2024

---

 1. [WordPress on VIP](https://docs.wpvip.com/wordpress-on-vip/)
 2. [WordPress multisite](https://docs.wpvip.com/wordpress-on-vip/multisites/)
 3. Subdomain and subdirectory structures

#  Subdomain and subdirectory structures

By default, all [WordPress multisite](https://docs.wpvip.com/wordpress-multisite/)
environments on the VIP Platform are configured with a subdirectory structure. The`
SUBDOMAIN_INSTALL` constant is defined at platform level in `wp-config.php` with
a default value of `false`. This value cannot be overridden, even by defining the
constant differently in `vip-config.php` or with any other methods.

Because the `SUBDOMAIN_INSTALL` is defined as `false`, [when a new network site is added](https://docs.wpvip.com/create-new-sites/)
the Site Address (URL) value must be a subdirectory of the domain that is assigned
to the main site (ID 1).

The Site Address (URL) for a network site can later be updated or launched with 
a custom domain, subdomain, or subdirectory (e.g. `example.com`, `two.example.com`,`
example.com/three`) with [the Network Sites launch tool](https://docs.wpvip.com/launch-a-site/begin-a-multisite-launch/).

A combination of network sites with both subdomain and subdirectory URL structures
can exist on the same multisite. For example:

 * A collection of network sites with only subdirectory structures (e.g., `example.
   com/one` and `example.com/two`).
 * A collection of network sites with assigned custom domains and subdomains (e.
   g., `example.com`, `another.example.com` and `one-more-example.com`).
 * A collection of network sites that include both subdirectory and subdomain structures(
   e.g., `example.com`, `example.com/one`, `another.example.com`, and `one-more-
   example.com/two`).

## Subdirectory paths

By default a subdirectory structure with a single segment path (e.g.,`example.com/
one`) is supported for the Site Address (URL) of network sites.

A Site Address (URL) subdirectory path with a maximum of two segments (e.g., `example.
com/one/two`) can be code-enabled by using the `site_by_path_segments_count` filter.

In the code example below, `$num_segments = 3;` sets the subdirectory structure 
to allow:

 * the custom domain
 * the first subdirectory
 * and the second subdirectory.

Integers higher than `3` are not allowed. A version of the code example below should
be added to `[/vip-config/client-sunrise.php](https://docs.wpvip.com/multisites/sunrise-php/)`:

/vip-config/client-sunrise.php

    ```lang-php
    function my_filter_site_by_path_segments_count( $num_segments ) {
            $num_segments = 3;
            return $num_segments;
    }
    add_filter( 'site_by_path_segments_count', 'my_filter_site_by_path_segments_count', 99 );
    ```

Last updated: August 08, 2024