I have an application that uses an AD service account domain\username. The service account is part of a security group that has read write execute permissions on a databases. I have the same group across multiple instances and it has been working for over 2 months. All of a sudden last week and the week before two of the 48 instances started getting authentication errors. The only way I have been able to fix it is to add the individual service account to the instance and give it the same permissions . Has anyone else ever run into this issue?
What is the difference in the output of xp_logininfo for one of the affected logins when you run it on one of the two servers affected versus one of the 48 servers not affected