login failed for user null

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login failed for user null

Karen Jackson

SSChasing Mays

Points: 636
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May 6, 2003 at 6:57 am

#82171

I received the below error message in the slq log at 3:10:07 AM:

Login failed for user '(null)'. Reason: Not associated with a trusted SQL Server connection.

I am a bit concerned since I have no jobs running at this time. Could this be a security issue or am I just worrying to much???

I check the logs for the sql server and Windows 2000 server and found nothing but the above error. Any place else I should look?

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K. Brian Kelley SSC Guru Points: 114532 More actions · Answer 1

This would be someone either trying to log in using a SQL Server account when you are set to Windows authentication only or someone trying to log in from an untrusted domain. It may be a cause for concern.

1) How many times did the error occur?

2) Could there have been other processes attempting to make a connection (say from a different server)?

3) Is this repeated over several days or is it just a one time thing?

K. Brian Kelley

http://www.truthsolutions.com/

Author: Start to Finish Guide to SQL Server Performance Monitoring

http://www.netimpress.com/shop/product.asp?ProductID=NI-SQL1

K. Brian Kelley
@kbriankelley

Karen Jackson SSChasing Mays Points: 636 More actions · Answer 2

Brian:

1 The error occurred only once

2. Re other servers causing issue - I checked all of my jobs and none run on that day or that time. And the only server access this server would be the backup server - which does not run on Sunday

3 And we are set for Windows and Sql authentication

It just was strange and the hour of the day caught my eye!! Of course who says hackers only work early in the morning??!!!

I will keep an eye on the log - i just wanted to make sure there was not another place to look for info about attempted logins

Thank you for your help Brian!

Karen