six demon bag

Wind, fire, all that kind of thing!


Automatic Updates Consuming 100% CPU

For a couple months now I've been observing the Automatic Updates service (wuauserv) causing high CPU load on hosts running Windows Server 2003 or Windows XP after new updates had been released. The problem vanished after the updates had been installed.

Apparently this is a problem with the Windows Update Agent, caused by inefficient handling of superseded updates. Installing the latest cumulative Internet Explorer update should resolve the problem.

Posted 12:13 [permalink]


Some Useful DFS Commands

List DFS replication groups:

dfsradmin rg list

List replicated folders in a replication group:

dfsradmin rf list /rgname:<REPL_GROUP>

See more ...

Posted 15:16 [permalink]


Interactive VBScript Shell

Python's interactive mode is very convenient, because you can try simple stuff without having to write it to a script first. Since I have to do a lot of VBScript lately, I wanted to have something like that for VBScript, too.

I found this blog post that has almost exactly what I wanted, except for line continuation. Which is what I added (for my own convenience). You can download the modified script here.

Update: Added an Import() procedure for loading/executing additional code from other VBScript files.

Update: vbsh can now be customized with an optional init script %USERPROFILE%\init.vbs.

Update: Added a function to look up keywords in the VBScript documentation (requires that script56.chm is installed in the current working directory, the Windows help directory, or one of the directories in the %PATH%). Note that you'll need the English language version of script56.chm, since other language versions use different internal paths.

Posted 18:03 [permalink]


Process Explorer Error: .NET Performance Counters Are Corrupt

Today I encountered the following error message on one of my servers (running Windows Server 2008) when I started Process Explorer:

The .NET performance counters on this system are corrupt. Run Exctrlst from the Microsoft Windows Resource Kit to repair them.

See more ...

Posted 11:58 [permalink]


Import other script files in VBScript

The VBScript language doesn't provide a feature for including other code files, so you can't easily build and import code libraries. However, the missing feature can be emulated using the ExecuteGlobal statement in a custom Import procedure.

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Posted 14:00 [permalink]


PrintBrm Error 0x8007007b

Running the following command for backing up a printserver configuration

"%SystemRoot%\System32\spool\tools\PrintBrm.exe" -B -S server -F "C:\path\to\backup.pbk"

gave me an error after listing the printer ports:

The following error occurred: 0x8007007b.
The filename, directory name, or volume label syntax is incorrect.

Check the eventlog for detailed information about the error which occurred.

Turns out, PrintBrm doesn't seem to like double quotes around the backup file name, at least not on Windows Server 2008 R2 SP1. I changed the command line to

"%SystemRoot%\System32\spool\tools\PrintBrm.exe" -B -S server -F C:\path\to\backup.pbk

and the backup ran without issues.

Posted 16:15 [permalink]


Attach to Internet Explorer

Internet Explorer exposes a COM object that can be controlled programmatically e.g. from a VBScript. The usual way is to create a new Internet Explorer instance and work with that:

 Set ie = CreateObject("InternetExplorer.Application")

However, sometimes you may want to use an already running instance instead of creating a new one.

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Posted 20:59 [permalink]


TSM BA Client 6.4 on Debian

Although IBM doesn't officially support its TSM client on Linux distributions other than SLES and RHEL the client works quite nicely on Debian. With version 6.4 you need at least the following 4 packages on AMD64 systems:

  • TIVsm-BA
  • TIVsm-API64
  • gskcrypt64
  • gskssl64

See more ...

Posted 00:46 [permalink]


Features on Demand in Server 2012

Back in the days of Windows 2000 Server and Windows Server 2003 it was common practice to copy the i386 folder from the CD to the server and change the SourcePath registry value, so you wouldn't have to shuffle installation media around for adding/removing Windows features. With the advent of Windows Vista and Server 2008 Microsoft introduced the component store. Now all Windows features were put on disk by default and simply had to be activated/deactivated. That increased the size of a Windows installation by factor 3-4, but on the other hand disk space had become rather inexpensive, so it wasn't that big a deal. And although the component store can be a little fragile at times it usually works quite well.

So far, so good. But what happened now with the release of Windows 8 and Server 2012? Someone at Microsoft decided that the component store took up too much space, so they introduced a new concept called "Features on Demand", which simply means that administrators can free disk space by removing components from the store. The .Net Framework 3.5 for instance was removed by default.

This is not a bad thing per se. However, the removed framework still shows up as an installable feature (e.g. in Server Manager), only now you're prompted for an alternate source path when you choose to install the framework. So what we have now is that the component store still eats up disk space (I didn't notice any significant reduction in used disk space) and we're back to either shuffling installation media around or copying sources to the local harddisk (eating up even more disk space).

Srsly, Microsoft?

Posted 15:06 [permalink]


Auditing Windows File ACLs

Sometimes you run into a situation where you need to determine the permissions on some directory tree. Be it to document or clean up permissions on the subdirectories of a share, to troubleshoot permission issues due to deleted accounts or groups, or whatever. Manually analyzing permissions is quite tedious, even when using standard tools like cacls or xcacls. The output of XCACLS.vbs isn't any better, but since it's a script, I considered modifying it to suit my needs … until I took an actual look at the script. I abondoned the thought afterwards.

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Posted 20:14 [permalink]


Creating blank VMs for PXE boot

For a customer project I had to create a couple dozen virtual machines on our Hyper-V cluster. The machines were to be installed via a 3rd party software deployment system (the customer doesn't use SCCM), so I had to assign static MAC addresses and enable PXE boot. The respective reservations on the DHCP server had to be created from the MAC addresses in a second step, because the customer domain is separated from the infrastructure domain.

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Posted 11:09 [permalink]