Whacked out Windows Service

I was supposed to blog about this sometime last year when we we're called in to be standby engineers for a large government organization in Singapore as they were trying to change their hardware for one of their SQL Server clusters (I had another similar incident today which reminded me to blog about it). When they didn't get the chance to successfully move to the new hardware, they rolled back their changes. Unfortunately, even their rollback process was screwed up as they couldn't bring up the services after doing a restore of their backup. Looking at the services applet in Windows, we couldn't start the service at all. It looks like their backup software was not able to resolve the long names in Windows, thus, introducing the tilde (~) character in the location of the executable for the service. The workaround for this is a registry hack. You can remove or change settings in your service by looking at this registry key

HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Services

Look for the service name and update the ImagePath key to the correct parameters that you would need for your service. In case you're thinking of deleting a service when it was not properly uninstalled or when it is totally screwed up, you can use the Windows command line tool sc to do the trick

RELOG tool in Windows Server 2008

I was configuring one of our customer's Windows Server 2008 to capture PerfMon counters for our analysis when I accidentally ended up storing the log file in binary format. Now, I didn't like the idea of reading the binary file as I will be importing it in a SQL Server database for Reporting Services to use. Although PerfMon has the ability to log directly to a SQL Server database using ODBC, I am not allowed to do anything outside of PerfMon. After digging thru some options in Windows Server 2008, I found out about the RELOG tool. The tool gives you the ability to extract out the counters from any format generated by PerfMon and store them in a different format. In my case, I had to store them as a CSV file



relog PerfMonCounterLog.blg -f csv -o PerfMonCounterLog.csv



I was trying to find more about this tool from Microsoft TechNet but couldn't find any (or maybe I wasn't just looking hard enough) although MSDN has something about the method called ReLog which does exactly the same thing. It's exposed as an API so you can call it from an application should you wish to do so

A thousand and one reasons for a generic error message.

I've spent a couple of hours trying to troubleshoot a clustered SQL Server 2008 installation. All I know is that it throws this error message after the installation process and does not give me any clue at all

The cluster resource ‘SQL Server (MSSQLSERVER)’ could not be brought online. Error: The group or resource is not in the correct state to perform the requested operation. (Exception from HRESULT: 0×8007139F)

Now, this might look like a dependency issue not working correctly but when I checked the Failover Cluster Management console on Windows Server 2008, all the dependencies are online and working as expected. As always, I started searching the Internet for related errors and couldn't find anything really specific except for the same thing - dependency issue. Now, here's what I found out. Since all of the dependencies - disks, MSDTC, IP and virtual server name - are all online, maybe it doesn't have anything to do with them after all. So the first thing I did was to do a PING test to the virtual server name for my clustered SQL Server instance and guess what I found out - there is another IP registered on the DNS server with the same FQDN (maybe a previous installation that wasn't cleaned up properly). I logged in to the DNS server and updated the IP address of my clustered SQL Server instance, ran ipconfig /flushdns on the node on which I am logged in and started the service in Failover Cluster Management. It worked! It just tells you that you should think outside of the box every now and then. It really pays to have that background in network and systems infrastructure every once in a while.

Want to free up disk space on your Windows Server 2008 system partition?

Here's one idea I got from this blog post. It came from KB 920730: How to disable and re-enable hibernation on a computer that is running Windows Vista. It certainly was not Windows Vista, but who would want to let their servers hibernate? Besides, Windows Server 2008 is listed on the Applies To section of the KB article. I've decided to give it a shot. Run this command on your command-prompt with administrative privileges

powercfg.exe /hibernate off

Now, if you happen to take a look at your system partition and show all the hidden files, you would see a hyberfil.sys file, a hidden system file located in the root folder of the system partition. The Windows Kernel Power Manager reserves this file when you install Microsoft Windows. The size of this file is approximately equal to the amount of RAM installed on the computer. Since we dont need hibernation on servers, you can just remove this file using the command above. Sometimes I wonder why everything is on the system partition when you don't even need them