Non Authentication Services related applications are causing high CPU utiilization resulting some failed logins.
An application is causing 100% CPU utilization on some servers causing some Unix enabled Active Directory Logons to fail when this occurs.
Is there a setting that will help to offset this?
You can use the vas.conf (/etc/opt/quest/vas/vas.conf) setting vascache-ipc-timeout.
This is known to help resolve issues with intermittent failures authenticating on high load systems.
The default is 5 seconds. You can increase it to 30 seconds by manually putting the configuration in the vas.conf file:
vascache-ipc-timeout = 30
You can also set it automatically by running:
/opt/quest/bin/vastool configure vas libvas vascache-ipc-timeout 30
You can go quite a bit higher than this on really busy systems but it is NOT recommended to push this to all of your systems.
30 is a good start point.
The other suggestion if possible is upgrading to get past recent fixes / enhancements for issues regarding high numbers of authentications occurring simultaneously. The current and recommended version as of this writing (April 18, 2018) 220.127.116.1133.