The most common causes of corruption of the Master database is probably an unplanned server reboot, like during a power outage, where the files that make up your Master database can become corrupted at the file level. Database Consistency Checker Utility results showing corruption.As a Database or System Administrator, it is essential that you to know the symptoms that may indicate the corruption or damage in your Master database so you can troubleshoot those types of issues correctly. If anything happens to the master database you can’t start or use your SQL Server instance. This means the all user and login details for the instance and the information about all the other databases on that instance are stored on the master database. The core information of master database is recorded in a physical file called master.MDF files, and the transaction logs are stored on to the masterlog.LDF file. SQL Server cannot start if the Master database is unavailable. This includes instance-wide metadata like logon accounts, endpoints, linked servers, system configuration settings, and records for the existence of all other databases and their file locations. This database records all the system-level information for your SQL Server system. The Master database is important to your SQL Server instance.

Sql master database corrupt