Large Memory Support in Windows Server 2003 x86

Have you ever built a x86(32-bit) Server with lets say 2GB of RAM and then later added more RAM bringing the total RAM to 3GB or 4GB? And then sat there scratching your head trying to figure out why an application such as SQL Server cannot utilize the memory beyond 2GB? I had this very issue happen the other week with Windows Server 2003 R2 SP2 (x86) and SQL Server 2005 Enterprise (x86) installed on a test server with 3GB RAM. I could not get SQL Server to allocate more than 1.7GB RAM and then remember the /PAE and /3GB switches in the Boot.ini file. I had completely forgotten about the settings since I've been working on mostly x64 systems in recent years. Once I added the switches and rebooted the system, SQL Server was able to allocate more memory and the problem was resolved.

Here is what's going on, Windows is not recognizing all of the memory in the system and it is unable to address it. Your next question should be does the hardware architecture support x64(64-bit), this may also be referred to as EMT64. 64-bit(x64) does not have the same limitations on memory as 32-bit(x86) and can address much more memory. Your system or software might not support x64, if that's the case then you're stuck using x86. If the system has an Intel processor, download the Processor Identification Utility from Intel to find the details of your processor and what it supports:
http://www.intel.com/support/processors/tools/piu/
I also have a blog post with information on the Intel Processor Utilities:
Intel Processor Identification Utility

Here are the steps to fix the memory issue so Windows Server 2003 can address the memory. Physical Address Extensions need to be enabled for the system, this is done by modifying the Boot.ini file. There are two switches that need to be present, maybe one depending on your system configuration. The switches are /PAE and /3GB. If the system has more than 16GB of RAM then remove the /3GB switches or the system won't see anything beyond 16GB. Also, these switches only apply to x86(32-bit) server operating systems. The Boot.ini can be edited by going to Control Panel > System > Advanced tab and clicking on the Settings button under Startup and Recovery then click Edit to change the Boot.ini settings. Be careful and double-check what you modify or the system might not boot. If the system doesn't boot after the switches are added, then boot to Safe Mode and change the settings back.

The following is an example of a Boot.ini file where the PAE and 3GB switches ha
ve been added:
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(2)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Windows Server 2003, Enterprise" /fastdetect /PAE /3GB

For more information, read the Microsoft KB article on the subject:
http://support.microsoft.com/kb/283037


If you're using Windows Server 2000 and SQL Server 2000, please refer to these Microsoft KB article for assistance.
How to configure SQL Server to use more than 2 GB of physical memory:
http://support.microsoft.com/kb/274750

SQL Server only uses 2 GB of memory even though the AWE option is enabled:
http://support.microsoft.com/kb/811891/

Adding Active Directory Users to SQL Server behind a Firewall

I ran into an issue the other day that I thought others might be interested in knowing. I built a new system and turned on Windows Firewall, then discovered that I couldn't add users from Active Directory to SQL Server. This server happens to be SQL Server 2005 w/SP3 on Windows Server 2003 R2 w/SP2, however this is not the important part. I did a little research on the ports used by SQL and Windows Server and found a bunch of information which is in a previous post, "Network Ports used by Microsoft Server Products". I ultimately decided to try a few key ports and determined that I needed to enable Port 445 for TCP traffic. Enabling TCP on Port 445 resolved my issue and I was able to add users from Active Directory once again. The port is listed under a default setting in the Windows Firewall Exceptions, it is under "File and Printer Sharing". Click on "File and Printer Sharing" and choose "Edit", then Enable Port 445. This should resolve the issue with adding Active Directory users to SQL Server.

Network Ports used by Microsoft Server Products

Here is some helpful information I stumbled upon this morning on the ports used for various Microsoft Server Products. At one time or another we've all tried to figure out the various ports used by different services to communicate between systems. Here is a list of some of the more common and some not so common ports used. Scroll to the bottom of the page to find a full list of the pieces mentioned in the support article.

http://www.microsoft.com/smallbusiness/support/articles/ref_net_ports_ms_prod.mspx