Apache mpm_itk_module not working with nextcloud

Nextcloud version (eg, 20.0.5): 22
Operating system and version (eg, Ubuntu 20.04): Debian 11
Apache or nginx version (eg, Apache 2.4.25): Apache 2.4.52
PHP version (eg, 7.4): 8.1

The issue you are facing:

Hello everyone,

I’m trying to set up the mpm_itk module for my nextcloud instance but it’s not working.

I’ve created a nextcloud user on my debian server and i want apache to use this specific user for my NC instance.

When i enable mpm_itk in my nextcloud.conf then i can’t access it the gui and i got this error

[Thu Mar 10 12:08:49.398192 2022] [mpm_itk:warn] [pid 471354] (itkmpm: pid=471354 uid=1001, gid=1001) itk_post_perdir_config(): setgid(33): Operation not permitted
[Thu Mar 10 12:08:49.398221 2022] [mpm_itk:warn] [pid 471354] Couldn't set uid/gid/priority, closing connection. 

i’ve got other website that works well with apache and mpm_itk so i guess the problem is not coming from the module itself but more from nextcloud and the permission of the nextcloud folder in var/www

the module is called that way in my nextcloud.conf

<IfModule mpm_itk_module>
       AssignUserId nextcloud nextcloud

and i’ve set ownership of the nextcloud folder to user nextcloud and group nextcloud.
in case i’ve had the user www-data in the nextcloud group but still not working.

the nextcloud folder (located in var/www) and its entire content is set to 750 regarding permissions.

for now i went back to www-data ownership and disabled the module in the nextcloud.conf

thanks a lot for your help.

could be link to a open debian-bug : https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=734814

i’m not sure if this really related to the issue you’re talking about.
it was working before (and actually it works with other websites on my server), and after some changes (mess actually) in my var/www/ folder regarding permission, i can’t get it to work anymore. and i can’t find what permission problem is causing this issue.