We have followed this https://docs.moodle.org/36/en/Upgrading to upgrade moodle from 3.5+ to 3.6.2+.
However, we find that once the upgrade is complete then no users (LDAP or local) are able to log in.
I am able to request a reset password link for my local admin account, and then I can get in. I have attempted to run LDAP syncs but this does not fix the issue.
I have checked all permissions and chowned/chmoded the directories as appropriate. We have also performed upgrades from previous versions in the past successfully.
Also, we have tried resolving the issue by removing the moodle data localcache and cache folders, but the problem persists.
Any help grately appreciated.