XF 2.0 User registration not working

[J_T]

I recently upgraded from XF 1.4 to XF 2.0.10. Didn't really run into any problems along the way but now with the board active I have noticed that user registration is not working. I tried to register as a new user and it redirects me back to the registration page, never completing. I've tried disabling the spam plugins, captcha, and age requirements with no change. XF is not reporting any errors. I have a Tapatalk plugin running as well as XF Enhanced search. I've tried disabling both with no change to registration. XF genereated emails seem to be working fine as well. What can look at next?

 

[Paul B]

Did you also test in a completely default style, with all custom JavaScript removed?

Typically issues of this nature are due to third party add-ons and styles, occasionally browser issues (try clearing the cache).

 

[J_T]

We're not using 3rd party styles. Just some small restyling of the default style.

 

[J_T]

I figured out the cause. Registration does not seem to work with memcached enabled. Here is what I had configured.

$config['cache']['enabled'] = true;
$config['cache']['sessions'] = true;
$config['cache']['config'] = [
    'servers' => [
        ['127.0.0.1', 11212]
    ]
];
$config['cache']['provider'] = 'Memcached';
$config['cache']['namespace'] = 'forum';

I commented that out and registrations started working. I also noticed the "processing" animation in the top right corner of the forum does not show up with memcached enabled.

I'm running this version of memcached with PHP 7.2.10:

php-pecl-memcached-3.0.4-2.el7.remi.7.2.x86_64
memcached-1.4.15-10.el7_3.1.x86_64
libmemcached-1.0.16-5.el7.x86_64

 

[Paul B]

XF 2 does support caching, including Memcached: https://xenforo.com/xf2-docs/manual/cache/#memcached