Professional Level Series - Top Server Admin No-No's - This series of 19 videos does a deep dive into mistakes a server admin, also known as a sysadmin, can make, as well as how to avoid or correct them.
Top Server Admin No-No's - Overview - Start Here for This Series
Top Server Admin No-No's - Placing a Server in the Wrong Security Classification
Top Server Admin No-No's - Sharing the Administrator or Root User Account
Top Server Admin No-No's - Failed Data Backups Go Unnoticed