Comprehending and Addressing the “include_once sunrise.php” Notification in WordPress Multisite

If you’re overseeing a WordPress Multisite setup and come across the warning below:

Warning: include_once(/home/u801461719/domains/scienceblog.com/public_html/wp-content/sunrise.php): Failed to open stream: No such file or directory in /home/u801461719/domains/scienceblog.com/public_html/wp-includes/ms-settings.php on line 47

Warning: include_once(): Failed opening '/home/u801461719/domains/scienceblog.com/public_html/wp-content/sunrise.php' for inclusion (include_path='.:/opt/alt/php82/usr/share/pear:/opt/alt/php82/usr/share/php:/usr/share/pear:/usr/share/php') in /home/u801461719/domains/scienceblog.com/public_html/wp-includes/ms-settings.php on line 47

This article aims to clarify the meaning of this error, the reasons it appears, and the methods to resolve it.

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What Is the sunrise.php Document?

Within WordPress Multisite networks, sunrise.php is a file utilized to load custom code at an early stage of the WordPress loading sequence, prior to the full initialization of the WordPress core. It’s primarily leveraged by plugins—particularly domain-mapping plugins—that aim to modify how individual sites within the network are initialized, especially in custom domain scenarios.

Typically, this file is found in the wp-content directory.

Reasons for the Warning

The warning signifies that WordPress tried to access the sunrise.php file during the multisite network’s initiation but could not locate it in the designated path.

The crucial excerpt here is:

Failed to open stream: No such file or directory

This implies that the file /home/u801461719/domains/scienceblog.com/public_html/wp-content/sunrise.php is either:

– Absent
– Incorrectly titled (e.g., a misspelling in the filename)
– Situated in the wrong directory
– Lacking permissions that obstruct its reading

Line of Code Causing the Warning

The warning arises from the wp-includes/ms-settings.php file at line 47, which generally includes the following code:

if (file_exists(WP_CONTENT_DIR . '/sunrise.php')) {
   include_once(WP_CONTENT_DIR . '/sunrise.php');
}

If the file is not present, the condition will still attempt to include it, resulting in the warning unless include_once() is appropriately surrounded by an existence verification (which is uncommon in earlier versions or custom setups).

Steps to Resolve the Warning

Here are some actions you can take to fix the error:

1. Determine the Necessity of sunrise.php

This file is not required by default for Multisite operation. It only becomes essential when specific plugins (like domain-mapping plugins) call for it. Thus:

– If you don’t utilize a plugin that requires sunrise.php, you may disregard the warning or adjust the code to mute it.
– If you do, follow the steps below to rectify it.

2. Locate or Restore sunrise.php

If you are aware that the file previously existed:

– Search other servers or backups for sunrise.php.
– Restore the file to wp-content/sunrise.php.

If the file is part of a particular plugin (for instance, WordPress MU Domain Mapping):

– Reinstall the plugin.
– Consult its documentation. Some plugins necessitate that you manually transfer sunrise.php from the plugin’s folder into wp-content.

Example:

cp wp-content/plugins/wordpress-mu-domain-mapping/sunrise.php wp-content/sunrise.php

3. Confirm Configuration in wp-config.php

If you are employing sunrise.php, make sure your wp-config.php file has the following directive before require_once(ABSPATH . 'wp-settings.php');:

define('SUNRISE', 'on');

This guarantees that the system correctly seeks and loads sunrise.php as intended.