How to prevent Brut force attack?

Hello and TYIA,
It looks like one of our Windows 2008 SBS is being attacked. In the security log, I see about 1400 event ID 4625 Audit Failures in the last 24 hours. They are all coming from different Ports and from IP addresses and use different usernames.
What is the best way to stop and prevent these attacks.
Although this is an SBS, we are not using the Exchange or the SharePoint services. We are only using it as an AD/File/Print server
Thank you,
dp
dp

Hi,
Since you are using Active Directory, I recommend you to use
Account Lockout Policy to avoid brute attacks.
By defining an
Account Lockout Threshold, we can control the number of failed logon attempts before an account gets locked out.
In addition, I also suggest you try to locate where these failed logon attempts generated from.
Audit failure events are not always caused by brute attacks, when some services, scheduled tasks or devices have cached old user passwords, audit failure events are generated, too.
Therefore, please make sure that the current passwords are used by those services or devices.
More information for you:
Account lockout policy overview
http://technet.microsoft.com/en-us/library/cc783851(v=WS.10).aspx
Troubleshooting Account Lockout
http://technet.microsoft.com/en-us/library/cc773155(v=WS.10).aspx
Many Audit Failure Event ID 4625
http://social.technet.microsoft.com/Forums/windowsserver/en-US/8f7ebcf5-2310-42c3-9b6a-20205a6c17ef/many-audit-failure-event-id-4625?forum=winserveressentials
Please feel free to let us know if there are any further requirements.
Best Regards,
Amy Wang

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There is some kind of control?
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uhm, i think it would be against Ironport Systems main purpose, that is to keep the appliances doing only its jobs. If you give a firewall, ppl will be able to use ironport to another tasks beyond MT task, and i think it's not wise...
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Ok, i understand what you say, but i cannot see the major usefulness of the built-in fw. If you really want your system to be safe, just dont run the stuff. Keep ssh and https disabled on the public interface.
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Good rules is better alternative to complex policy.
Combine password history with time interval between changes.
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check out this link below:
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Not defined.
Discussion
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Location
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tuolumne wrote:
Kostya1992 wrote:
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Brothers credit journey of BRUTE FORCE (cont)

I remember that crazy wacko app spree like yesterday

tuolumne wrote:
Kostya1992 wrote:
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