Another one-liner in Windows PowerShell

I did mention that I have been trying to convert my VBScript files to PowerShell scripts due to ease of coding. One of them happened to be a script that iterates a folder containing logs, reads the contents of the log files and appends them to a text file (I was actually trying to consolidate all the RADIUS logs for parsing and storage in a database). In VBScript, here's how it is written

Const ForReading = 1
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set folder = objFSO.GetFolder("d:\a")
Set outfile = objFSO.CreateTextFile("d:\testout.txt")

for each file in folder.Files
Set testfile = objFSO.OpenTextFile(file.path, ForReading)
Do While Not testfile.AtEndOfStream
line=testfile.ReadLine
'write to a single output file
outfile.writeline(line)
Loop
testfile.close
Next

outfile.close
Set objFSO = Nothing
Set folder = Nothing
Set outfile = Nothing

Here's how you can do it in PowerShell - with the cmdlet aliases

ls d:\a\ gc ac d:\testout.txt

This should be more than enough reason to learn PowerShell as a system administratior. More to come

Renaming your domain controller hostname

This is not really recommended if you think about it. How many of you eventually decided that one day, you need to rename your domain controller? I bet no one. But there are unusual cases where you do not have any other choice but to do it.

That's what happened to me when I was building my virtual image of a Windows Server 2003 domain controller. I accidentally plugged in my automated installation CD. To my surprise, the installation has generated a random name for my machine. Although I could demote the domain controller, change the hostname, and promote it back, it would be very time consuming with all those reboots and manual steps. Searching thru Google gave me this site which recommends the use of the Netdom.exe tool. You do need to install the Windows Support Tools to use this tool. To change the hostname of the domain controller, open the command prompt associated with the Windows Support Tools. Then, run the following command

netdom computername oldhostname.domainname /add:newhostname.domainname

Although there are other instructions mentioned in the article, I only needed this command. After rebooting the server, I ran dcdiag.exe (Domain Controller Diagnostics Tool) and netdiag.exe(Network Connectivity Test Tool in the Windows Support Tools command prompt to validate the connectivity to the domain controllers. Knowing that you have the right tools available would make life a bit easy for any professional - whether in IT or not

Windows Update Explained

For those who administer or manage WSUS or simply do patch management, here's a documentation from TechNet written by the Windows Update Product Team to better understand updating behavior and what Microsoft is trying to do with Windows Update. While I rely so much on the WindowsUpdate.log file and/or the WSUS reporting feature to troubleshoot patch deployment issues, it's best to understand what is happening under-the-hood to get a better picture

Why WIndows Instant File Initialization for SQL Server 2005 matters

SQL Server 2005 supports Database Instant File Initialization which skips zeroing out data pages that can reduce the time when performing operations like creating databases, adding files to an existing database, increasing the size of an existing database file manually or thru autogrowth or restoring a database or filegroup. I've written an article in MSSQLTips.com highlighting it's importance both in a disaster recovery and operational performance scenarios. I ran a few tests as well to simply answer a query in the forum regarding the topic. I ran my tests on a VMWare image on a DELL PowerEdge 2650 with 4 X 2.8 GHz CPU and 3GB RAM. The image is running Windows Server 2003 Enterprise Edition with SQL Server 2005 Enterprise Edition as this is an "Enterprise Edition only" feature. I've created a 10GB-sized database which took only 0.1 seconds using instant file initialization. Without it, the same took about 2:10 minutes. Imagine doing a restore for a 500GB-sized database. That will save you a lot of time on the restore process. Same goes with file auto growth. The difference in the amount of time it takes to do a restore would definitely matter when you're dealing with very large databases. Imagine trying to restore a 500GB-sized database. You'll probably agree after trying it out for yourself