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Server-Level Roles

SQL Server provides server-level roles to help you manage the permissions on a server. These roles are security principals that group other principals. Server-level roles are server-wide in their permissions scope. (Roles are like groups in the Windows operating system.)

Fixed server roles are provided for convenience and backward compatibility. Assign more specific permissions whenever possible.

SQL Server provides nine fixed server roles. The permissions that are granted to the fixed server roles cannot be changed. Beginning with SQL Server 2012, you can create user-defined server roles and add server-level permissions to the user-defined server roles.

You can add server-level principals (SQL Server logins, Windows accounts, and Windows groups) into server-level roles. Each member of a fixed server role can add other logins to that same role. Members of user-defined server roles cannot add other server principals to the role.

Fixed Server-Level Roles

The following table shows the fixed server-level roles and their capabilities.

Fixed server-level role Description
sysadmin Members of the sysadmin fixed server role can perform any activity in the server.
serveradmin Members of the serveradmin fixed server role can change server-wide configuration options and shut down the server.
securityadmin Members of the securityadmin fixed server role manage logins and their properties. They can GRANT, DENY, and REVOKE server-level permissions. They can also GRANT, DENY, and REVOKE database-level permissions if they have access to a database. Additionally, they can reset passwords for SQL Server logins.

** Security Note ** The ability to grant access to the Database Engine and to configure user permissions allows the security admin to assign most server permissions. The securityadmin role should be treated as equivalent to the sysadmin role.
processadmin Members of the processadmin fixed server role can end processes that are running in an instance of SQL Server.
setupadmin Members of the setupadmin fixed server role can add and remove linked servers by using Transact-SQL statements. (sysadmin membership is needed when using Management Studio.)
bulkadmin Members of the bulkadmin fixed server role can run the BULK INSERT statement.
diskadmin The diskadmin fixed server role is used for managing disk files.
dbcreator Members of the dbcreator fixed server role can create, alter, drop, and restore any database.
public Every SQL Server login belongs to the public server role. When a server principal has not been granted or denied specific permissions on a securable object, the user inherits the permissions granted to public on that object. Only assign public permissions on any object when you want the object to be available to all users. You cannot change membership in public.

Note: public is implemented differently than other roles. However, permissions can be granted, denied, or revoked from public.

Permissions of Fixed Server Roles

Each fixed server role has certain permissions assigned to it. For a chart of the permissions assigned to the server roles, see Database Engine Fixed Server and Fixed Database Roles.

Important

The CONTROL SERVER permission is similar but not identical to the sysadmin fixed server role. Permissions do not imply role memberships and role memberships do not grant permissions. (E.g. CONTROL SERVER does not imply membership in the sysadmin fixed server role.) However, it is sometimes possible to impersonate between roles and equivalent permissions. Most DBCC commands and many system procedures require membership in the sysadmin fixed server role. For a list of 171 system stored procedures that require sysadmin membership, see the following blog post by Andreas Wolter CONTROL SERVER vs. sysadmin/sa: permissions, system procedures, DBCC, automatic schema creation and privilege escalation - caveats.

Server-Level Permissions

Only server-level permissions can be added to user-defined server roles. To list the server-level permissions, execute the following statement. The server-level permissions are:

SELECT * FROM sys.fn_builtin_permissions('SERVER') ORDER BY permission_name;  

For more information about permissions, see Permissions (Database Engine) and sys.fn_builtin_permissions (Transact-SQL).

Working with Server-Level Roles

The following table explains the commands, views, and functions that you can use to work with server-level roles.

Feature Type Description
sp_helpsrvrole (Transact-SQL) Metadata Returns a list of server-level roles.
sp_helpsrvrolemember (Transact-SQL) Metadata Returns information about the members of a server-level role.
sp_srvrolepermission (Transact-SQL) Metadata Displays the permissions of a server-level role.
IS_SRVROLEMEMBER (Transact-SQL) Metadata Indicates whether a SQL Server login is a member of the specified server-level role.
sys.server_role_members (Transact-SQL) Metadata Returns one row for each member of each server-level role.
sp_addsrvrolemember (Transact-SQL) Command Adds a login as a member of a server-level role. Deprecated. Use ALTER SERVER ROLE instead.
sp_dropsrvrolemember (Transact-SQL) Command Removes a SQL Server login or a Windows user or group from a server-level role. Deprecated. Use ALTER SERVER ROLE instead.
CREATE SERVER ROLE (Transact-SQL) Command Creates a user-defined server role.
ALTER SERVER ROLE (Transact-SQL) Command Changes the membership of a server role or changes name of a user-defined server role.
DROP SERVER ROLE (Transact-SQL) Command Removes a user-defined server role.
IS_SRVROLEMEMBER (Transact-SQL) Function Determines membership of server role.

See Also

Database-Level Roles
Security Catalog Views (Transact-SQL)
Security Functions (Transact-SQL)
Securing SQL Server
GRANT Server Principal Permissions (Transact-SQL)
REVOKE Server Principal Permissions (Transact-SQL)
DENY Server Principal Permissions (Transact-SQL)
Create a Server Role