WordPress Multisite: How to fix error "too many redirects"

wordpress-multisite-internal-redirect-loop.md

WordPress Multisite: How to fix error "Request exceeded the limit of 10 internal redirects"

I am running a WordPress multisite network with sub-directory setup. When I check my error.log file, it is full of entries like this one:

Request exceeded the limit of 10 internal redirects due to probable configuration error. Use 'Limit InternalRecursion' to increase the limit if necessary. Use 'LogLevel debug' to get a backtrace.

The problem was, in my case, one specific rewrite rule in the .htaccess file.

Problem description

If you open the network admin backend an go to the network admin page, then WordPress will suggest you some directives that you should put in your .htaccess file. In my case, these directives look like this:

RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# uploaded files
RewriteRule ^([_0-9a-zA-Z-]+/)?files/(.+) wp-includes/ms-files.php?file=$2 [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]

Imagine someone requesting a URL like http://example.com/wp-content/file.txt.

If file.txt exists on the server, then Apache will deliver the file to the client because of these directives:

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]

If, however, file.txt does not exist as a static file on the server, these rules will not fire. But the following rewrite rule will attempt to rewrite the request URI:

RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]

But in our example, the requested URL http://example.com/wp-content/file.txt will just be rewritten to itself. Then, Apache tries to process this request again, going through the rules in the .htaccess file again and again. This results in the internal redirect loop.

Solution

What we had to do was to make sure that the aforementioned rewrite rule does not fire anymore for request URIs that begin with /wp-content/. One way to achieve this is to remove the question mark from this directive. So the new rewrite rule would look like this:

RewriteRule ^([_0-9a-zA-Z-]+/)(wp-(content|admin|includes).*) $2 [L]

Another possibility would be to add an additional rewrite condition before this rewrite rule. This would look like this:

RewriteCond %{REQUEST_URI} !^/wp-(content|admin|includes).*$
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]

If you go for this solution, then you might have to adapt the rewrite condition if your RewriteBase is something else than /.

new .htaccess file

I went for the first solution. Here's my new .htaccess file.

RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# uploaded files
RewriteRule ^([_0-9a-zA-Z-]+/)?files/(.+) wp-includes/ms-files.php?file=$2 [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)(wp-(content|admin|includes).*) $2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)(.*\.php)$ $2 [L]
RewriteRule . index.php [L]

I haven't had any of these errors since I applied these changes.

Bug report

This bug has been reported to the WordPress developers quite some time ago. I hope there will be a fix soon.

Help me family, I have faced the same error, when I came to this page and found, redirection stopped, but frontend is showing me this error,
"Please refresh your browser or waiit and try again after some minutes!"
What can I do to solve that error message.
Here is my .htaccess codes

BEGIN WordPress Multisite

Using subfolder network type: https://wordpress.org/documentation/article/htaccess/#multisite

RewriteEngine On
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
RewriteBase /
RewriteRule ^index\.php$ - [L]

add a trailing slash to /wp-admin

RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteCond %{REQUEST_URI} !^/wp-(content|admin|includes).$
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).) $2 [L]
RewriteRule . index.php [L]

END WordPress Multisite

Hello,
I am new to coding, so most of what we have here is Greek to me. I'm just a 59 year-old journalist trying to put his sites together. I have been working with multisites and hd no issues until I changed server. Migration was cool. Everything worked fine. Then my domains were transferred and after transfer was complete, I couldn't even get into my wordpress multisite backend.
I am told it's the code in my .htaccess file. I've reproduced here below. Could anyone help me figure out the problem? I am desperate.

BEGIN WordPress

RewriteEngine On RewriteBase / RewriteRule ^index\.php$ - [L] RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule . /index.php [L] # END WordPress # php -- BEGIN cPanel-generated handler, do not edit # Set the “ea-php80” package as the default “PHP” programming language. AddHandler application/x-httpd-ea-php74___lsphp .php .php7 .phtml # php -- END cPanel-generated handler, do not edit

While the notion of removing the "?" as a fix might initially seem viable, a closer inspection reveals its shortcomings. Let's delve into the intricacies:

^([_0-9a-zA-Z-]+/)(wp-(content|admin|includes).*) $2 [L]

This regular expression breakdown is as follows:

• ^ anchors the pattern to the start of the string.
• ([_0-9a-zA-Z-]+/) matches a string followed by a "/", such as "subpath/".
• (wp-(content|admin|includes).*) matches "wp-content", "wp-admin", or "wp-includes", followed by any characters.

Matches:

subsite1/wp-content/plugins/
subsite2/wp-content/plugins/

Doesn't Match:
wp-content/plugins/

The "?" was initially included to optionally match the part before "wp-*", ensuring compatibility even if there's nothing preceding it.

However, an alternative approach i found proves to be more comprehensive:

RewriteRule ^(?:[_0-9a-zA-Z-]+/)?(wp-(?=content|admin|includes).*) $2 [L]

Here's why it excels:

• (?:[_0-9a-zA-Z-]+/)? renders the preceding pattern (string followed by "/") optional without capturing it (no capture = little more performance, if im already doing it, then right).
• (wp-(?=content|admin|includes).*) matches "wp-" followed by "content", "admin", or "includes", succeeded by any characters (this makes so the group (content|admin|includes) doesn't match the content, admin and includes twice.

Matches:

wp-content/plugins/
subsite1/wp-content/plugins/
subsite2/wp-content/plugins/

It's a more robust solution compared to simply removing the "?".

Alternatively, placing RewriteCond %{ENV:REDIRECT_STATUS} ^$ in front would work as well. However, I aimed for a more universal approach that could be compatible with non-Apache web servers.

https://regex101.com/r/gNqD8P/1 (initial)
vs
https://regex101.com/r/Tq9zik/1 (removed ?)
vs
https://regex101.com/r/n2bGBc/1 (mine)