Analyzing the Login Loop bug

[musicmaster]

The Admin Login Loop bug is a bug that has been around for many years. Many PS webshop owners have seen it at least once. In an effort to solve it I have grabbed the last occasion that it occurred to me to make some analysis. I hope that others will grab the opportunity to build on this effort so that finally we can leave this problem behind us.

 

I first tried emptying the cache and deleting the cookies: no result.

 

Then I tried with the Shop Rescue page of Prestools to switch some configuration flags to see whether any had an effect. It appeared that switching PS_HTACCESS_DISABLE_MULTIVIEWS on solved the bug. 

 

However, as other webshops on this server were running ok it appeared unlikely that this Apache feature was the culprit. So I tried deleting .htaccess. That worked too. So I compared this .htaccess with that from another - working whop. However, I couldn't find any difference: everything seemed ok.

 

Of course a Prestashop cannot with a .htaccess file. So I went in the backoffice to regenerate it. Initially that resulted in two errors (my shop language is Dutch so the text may not be exactly correct)

 - the route is not valid

 - route to modules: incorrect value.: 

 

When I pressed save to generate a .htaccess file a second time there was no error.

 

That left the question where those "route" errors came from. So I compared a dump of the configuration table taken before with a dump taken after the .htaccess generation. It appeared that the following values had been added:

 

 

402, NULL, NULL, 'PS_ROUTE_product_rule', NULL, '2016-12-11 10:04:39', '2016-12-11 10:04:39'),

(403, NULL, NULL, 'PS_ROUTE_category_rule', NULL, '2016-12-11 10:04:39', '2016-12-11 10:04:39'),

(404, NULL, NULL, 'PS_ROUTE_layered_rule', NULL, '2016-12-11 10:04:39', '2016-12-11 10:04:39'),

(405, NULL, NULL, 'PS_ROUTE_supplier_rule', NULL, '2016-12-11 10:04:39', '2016-12-11 10:04:39'),

(406, NULL, NULL, 'PS_ROUTE_manufacturer_rule', NULL, '2016-12-11 10:04:39', '2016-12-11 10:04:39'),

(407, NULL, NULL, 'PS_ROUTE_cms_rule', NULL, '2016-12-11 10:04:39', '2016-12-11 10:04:39'),

(408, NULL, NULL, 'PS_ROUTE_cms_category_rule', NULL, '2016-12-11 10:04:40', '2016-12-11 10:04:40'),

(409, NULL, NULL, 'PS_ROUTE_module', 'module/{module}{/:controller}', '2016-12-11 10:04:40', '2016-12-11 10:04:40');

 

I checked another - working - shop. There these values were already there. Maybe the problem was that this was a new shop. I don't know. Anyway, the bug has disappeared.

 

BTW. it is rather easy to see which values in the configuration table of your shop were changed most recently: just open the ps_configuration table in phpmyadmin and sort it on the date_upd field with most recent first.

 

If you have a problem with a login loop, please mention it here and tell everyone whether this helps you to find a solution. If not, we may find  way tio help you.

Edited December 13, 2016 by musicmaster (see edit history)