Sql-server – logins without any users

What you will have to do is connect to the instance that has a mis-matched SID, and you'll have to recreate the login and specify an explicit SID. For instance, on the instance where you have the orphaned user and the following returns the user:

exec sp_change_users_login 'report';
go

Copy the SID from the column UserSID. And if you already have an existing login that you want to preserve the name from on that instance, you can't. There is no way to ALTER LOGIN and change the SID. So, you will need to drop the login and recreate it:

drop login YourLogin;
go

create login YourLogin
with
    password = 'password',
    check_policy = off,     -- simple password and no check policy for example only
    sid = 0xC26909...................;
go

Again, you will want to set the sid parameter of CREATE LOGIN to the UserSID you retrieved from executing sp_change_users_login with the report.

Note: You will want to set the password on this/these replica(s) to the same so that you don't have a password mismatch between replicas.

I am assuming that your login(s) in question here are SQL Server logins, as this shouldn't be a problem for Windows Auth domain accounts because the SIDs should be the same on each instance.

You could also leverage contained databases here and have the database principal authenticate at the database level. That way you wouldn't have to worry about orphaned users.

Here is some documentation on this:
BOL reference on Management of Logins and Jobs for the Databases of an Availability Group
KB article on How to transfer logins and passwords between instances of SQL Server

Also, this should go without saying, but test this out in a development/QA environment to verify and ensure proper functionality before hitting production.

to do it correctly is not very simple, although once setup, your done.

Data users or application roles default have database scoped permissions. Database users are linked to Logins and therefore can have server wide permissions from their Login. Application roles aren't linked and can only get server wide permission by using a form of impersonation.

Any way to give these server scope permissions by means of impersonating will fail by default.This is by design.

You have 2 options:

1. Tell SQL Server that you as a DBA trust any user in that database to have privilegde escalation to server wide permission if impersonation is used. You acomplish this by setting the option TRUSTWORTHY to ON However if you don't fully understand what this option does first read: SQL Server 2012 Best Practice Whitepaper (Specifically page 18 and 19 about "Database Ownership and Trust")
2. Use signed stored procedures to accomplish your task.

I'll first give you the example of option 1:

CREATE LOGIN [appRoleProxy] WITH PASSWORD ='1234abcd!@'
GO

EXEC sp_addsrvrolemember    @loginame='appRoleProxy',
                            @rolename='securityadmin'

GO

CREATE DATABASE [Stefaan]
go

ALTER DATABASE [Stefaan] SET TRUSTWORTHY ON
GO

USE [Stefaan]
GO

--add the proxy account to the dbo role since your stored procedure will be running in the context of this account and is also accessing your user database.
ALTER ROLE [db_owner] ADD MEMBER [appRoleProxy]
GO

CREATE APPLICATION ROLE appRole WITH PASSWORD ='Passw0rd!';
GO

CREATE PROCEDURE dbo.usp_testproc 
@LoginName nvarchar(128),
@Password nvarchar(128),
@DBName nvarchar(128)
WITH EXECUTE AS 'appRoleProxy' --Impersonate a SQL server login with the proper server level permissions
AS
DECLARE @SQL varchar(max)
BEGIN
    IF NOT EXISTS ( SELECT  name
                    FROM    sys.server_principals
                    WHERE   name = @LoginName )
        BEGIN
            SET @SQL = 'CREATE LOGIN [' + @LoginName + '] WITH PASSWORD = '''
                + @Password + ''', DEFAULT_DATABASE=[' + @DBNAME
                + '], CHECK_EXPIRATION=OFF, CHECK_POLICY=OFF';
            EXECUTE(@SQL);
        END

    IF NOT EXISTS ( SELECT  name
                    FROM    sys.database_principals
                    WHERE   name = @LoginName )
        BEGIN
            SET @SQL = 'CREATE USER [' + @LoginName + '] FOR LOGIN ['
                + @LoginName + ']';
            EXECUTE(@SQL);
        END

    IF EXISTS ( SELECT  name
                FROM    sys.server_principals
                WHERE   name = @LoginName )
        BEGIN
            EXEC sp_addsrvrolemember @LoginName, 'securityadmin'
        END
END
GO

GRANT EXECUTE ON [dbo].[usp_testproc] TO [appRole]
GO


sp_setapprole   @rolename='appRole',
                @password='Passw0rd!'



EXEC usp_testproc 'testlogin','password23@','stefaan'

Now for an example of option 2 I'd like to point out a answer a gave on another question: Msg 4834 “You do not have permission to use the bulk load statement”