How to check a SQL Login is part of the SYSADMIN role

Question: As part of  a regular SQL Server Violations reporting and checking any vulnerabilities on SQL Servers, I run regular scans and report on elevated server roles.  What is an efficient method to identify if a login is using the sysadmin role?

Answer:  I use the IS_SRVROLEMEMBER  function , which allows you to check on various server roles. As well as sysadmin , it is possible to also check on  serveradmin,dbcreator,setupadmin,bulkadmin,securityadmin,diskadmin and processadmin.

The IS_SRVROLEMEMBER  returns either a value of 1 or 0. 1 = the login is a member of the role  0= the login is not a member of the role.

This an example of how to check if the 'BUILTIN\Administrators' login is a member of the sysadmin role, this is by using the login option

 SELECT IS_SRVROLEMEMBER('sysadmin', 'BUILTIN\Administrators'); 

This is an example if the CURRENT login is a member of the sysadmin group 

SELECT  IS_SRVROLEMEMBER ('sysadmin');

Read more on managing the sysadmin role

Drop sysadmin with ALTER SERVER ROLE and DROP MEMBER ...

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