How to fix Kerberos authentication failure due to kerberos ticket size

This article describes that when a user belongs to a large number of groups (i.e. 450+) on Windows, the user may encounter the Kerberos authentication failure

Scope

FortiProxy.

Solution

Adjust the ‘max-message-length’ setting accordingly:

config web-proxy global
set max-message-length 64
next
end

By default, the setting is set to 32. Increase the size accordingly.