Restive Technology

Boot Analysis

The MBR is the first 512 bytes of your hard drive.  All x86 systems that don’t use EFI start booting from this sector.

There is a lot of information on the web about it already, but I am working on a program that will decode the MBR and display its secrets for you to see.  It is entirely written in JavaScript, PHP and HTML (with a little CSS for flavor), and it should be ready to post in a few weeks.

Multiboot DVDs

Imagine this – You boot from one DVD, and a menu comes up:

1. Install Windows

2. Boot BartPE

3. Boot from Dos

4. Boot from Linux

5. Run Memtest86+

6. Anything you can think of

This is a reality – using CDSHELL or GRUB4DOS.   I’ve been intrigued by the different ways in which to create a multiboot DVD or USB stick, and these are the two ways I’ve found that seem the most solid.  Don’t be fooled by the name GRUB4DOS, because it can boot Windows and Linux just as well as DOS.  Sorry, MacOS users, but this doesn’t apply to you.

If you want to create a multiple-installers dvd, look no further than http://flyakite.msfn.org because it is the definitive resource on using CDShell to install multiple versions of Windows from one DVD.

For those of you who want to run Linux or boot from USB, I believe GRUB4DOS is your best bet.  I’d like to spend more time and post details about how to do these things, hopefully when I have more time.  If you are the go-to guy for fixing computer problems in your network of friends, you will find it really helpful to have multiple ways to boot a dead system.  The best thing about GRUB4DOS is that you have so many options.  If you want to boot the same images via PXE, USB or DVD, you can create the same basic structure and make it work on all three the same way.  CDShell, on the other hand, can only be used from DVD or possibly from another bootloader like GRUB4DOS.

Windows IP Configuration and .NET rrdtool

IP configuration difficulties

I have two new interesting things to post today.  The first is a solution to a strange problem.  A coworker of mine suddenly found that his laptop would not connect to the internet.  I opened a command window to see if he got any IP information, and I saw:

C:\Documents and Settings\username>  ipconfig

Windows IP Configuration

C:\Documents and Settings\username>

That’s it.  No adapters were listed at all.  I ran across this experts-exchange article that helped solve the problem.

I only had to:
regsvr32 netshell.dll
regsvr32 netcfgx.dll
regsvr32 netman.dll

But in addition, if that doesn’t work for you, there are other steps you can take.  One user booted into safe mode and removed the network card drivers, then let Windows detect them again.  Another user had to perform the following:

- Reinstalled all wireless/wired drivers from Dell
- Reset my Winsock using netsh: http://support.microsoft.com/kb/892350
- Reinstalled Winsock/Winsock2 using these instructions from MS: http://support.microsoft.com/default.aspx?scid=kb;en-us;817571
- Ran the 3 DLL register commands from the first post.
- Ran Winsock XP Fix for good measure: http://www.snapfiles.com/get/winsockxpfix.html
- Rebooted Windows

NHawk to the rescue for .NET and rrdtool on Windows

I would like to write a program in C# (.NET) that will automatically update RRD graphs on Windows.  The incredibly useful rrdtool and its windows binary can be used to update rrd graphs on the same machine they’re graphing.  I want to do this for performance reasons and for scalability.  I don’t need to have all the graphs on one server, the way we run cacti currently.

I found a wrapper project, NHawk, that allows me to write RRD commands using .NET objects.  The only thing that I can’t figure out how to do is GPRINT.  I’m about to email the author and find out if there is an update.

VMWare eth0 disappears in Ubuntu Linux after using Converter

Whenever I migrated a linux server using the VMware Converter, my ethernet devices disappeared. I found a quick and easy way to restore them without any fancy work. Just delete (or move) the file /etc/udev/rules.d/70-persistent-net.rules. This file is used to associate the eth devices with a mac address so that they always come up the same way. When VMware converts a machine, it assigns a different mac address to the virtual ethernet adapter, so this file needs to be deleted.

Thanks to http://techblog.romero.id.au/2009/06/ubuntu-missing-eth0-after-cloning-in-vmware/ for the explanation.

How to delete a file with a space at the end

A long time ago, in a galaxy far far away, Windows always ran on DOS.  Furthermore, file names longer than 8 characters with a 3 character extension were not allowed.  Nor were files that ended in a space.

When Microsoft decided to extend the file name length to more than 8.3 characters, they made the latter backwards-compatible with the former dos ways.  Therefore, a file name like

“My Pictures”

was interpreted in 8.3 format as

“MYPICT~1″

Normally, this feature is never used, because modern day Windows programs use long file names with spaces and other symbols with no problem.  But today, I found an anomaly, a directory of my friend’s pictures that was created (in Unix) with a space at the end, and Windows simply refused to delete it. All the history of Windows and DOS came rushing back to me in one sweet moment.

I tried all the classic ways to do it.  Command line, reboot, try to rename the directory before deleting it.  The problem was, Windows could tell that the file had a space at the end.  I would type ‘del Mich<tab>’ and Windows would fill in the rest of the prompt to say ‘del “Michelle “.’  But I couldn’t delete it until I stumbled across a simple solution:

First, use “DIR /X” to find the 8.3 filename.  Then use del to delete that simple 8.3 name.

Simple, yet profoundly historic.  Much as Microsoft has tried to hide DOS and render it irrelevant in Windows XP, it still shows its roots now and then.

Dell OpenManage on ESX 3.5

I use Nagios to monitor services. I use a script called check_openmanage to monitor the Dell OpenManage agent on ESX servers using SNMP.  I noticed that it was returning the result

“UNKNOWN: (SNMP) OpenManage is not installed or is not working correctly”

In order to diagnose the problem, I had to connect to the ESX server via SSH.  OpenManage 5.5 runs a few services on the ESX backend.  To check the services, I ran:

/sbin/chkconfig –list |grep dsm

Those services looked fine… so I ran another command for more detail

/sbin/service –status-all |grep dsm

Aha,  dsm_sa_snmp32d was not running.  But I didn’t know the name of the service attached to it.  I found the file:

find / -iname dsm_sa_snmp32d

/opt/dell/srvadmin/dataeng/bin/dsm_sa_snmp32d

OK, I know where that file is… but how does Dell want me to run it?

ls /opt/dell/srvadmin/dataeng/bin

I see “dataeng” as a lone file without an extension.  It is probably the executable that starts the other services.  Sure enough if I ls /etc/init.d I find the same file.

/etc/init.d/dataeng restart

And everything’s working again!

Why did it happen?  Who knows.  It was working fine for months before, so I will just shrug it off as one of those things.  I don’t have time to mess with it any further.

Tools of the Trade

A Windows user is nothing without his tools.  I mostly manage Windows systems –  I use Linux too, but mostly Windows.

With that in mind, here are my top 17 favorite Windows tools, all free of charge.  Many of these will be in other lists, and that’s good, it means they are tools that a lot of people recommend.  Others are more rare pieces of software, treasures I have found useful.

There are obviously many alternatives to this list, but the reason I chose each of these is because they stand apart from others I’ve found in terms of features, user interface, ease of use, and stability.  Perhaps tool X doesn’t do what you want because it doesn’t have feature Y… but for the most part, these products do everything I need them to do, so I recommend them.

1. jZip – A free alternative to WinZip.  It also supports more options, like reading .iso format.  Very useful.

2. FileZilla – FTP Client (and the server is good too!)  Not only is it free, but it’s also the best FTP client I have found.  It supports SSL and you can FTP through SSH if you have a linux server–very useful.

3. Paint.NET – A free replacement for Photoshop (or Paint if you’re still using that).  Supports simple layers and most of the common tools also found in Photoshop.

4. Firefox – Many people don’t bother to choose a browser, since Windows has been bundled with Internet Explorer since 1998.  But this is the browser of choice for people who do.  Supports tabs, error checking (for javascript), password saving, profiles, and is considered more secure than IE.  Beware, though, if you go to a lot of sketchy sites, you might eventually pick up a bug with any browser.

5. PrimoPDF – A driver that allows you to print anything to a PDF file instead of a printer.  Unfortunately the newer version has an extra dialog box after you create the file, which is a completely unnecessary hassle.

6. Thunderbird – A free and better alternative to Outlook, but the calendar system is a plug-in that you have to install, and it isn’t as good as Outlook’s calendar.  However, go web 2.0 and you can have GMail, which completely tramples both Outlook and Thunderbird in terms of accessibility and ease of use.

7.  DriveImage XML – Create an image of your Windows OS while it’s running?  No problem.  Works with Server 2003, XP, and later systems.  It uses Volume Shadow Services to perform the image in the background, so you can continue to use the computer while it’s imaging.  Amazing technology.  The restore, however, is a whole different bag of worms.

8. AVG Antivirus Free version – For home users, this is a good choice.  Avast! is another option, but I prefer AVG because it doesn’t wake you up in the middle of the night by playing “Virus Database Updated!”  through your speakers.  Fair warning though, I seem to remember AVG has a web link protection that should be disabled, as it slows things down a lot while surfing the web.

True story:  My wife and I live in a studio, so we share the room with the computer we use for watching movies.  We have to turn the volume up to watch DVDs because of their dynamic range, so we watched a movie and then went to sleep.  You can see where this is going.  About 3am, Avast! decided to update the virus database and when it was done, it announced the fact to us at the top of our stereo’s volume.  We were wide awake after that.  Thanks Avast!

9. DosBox – Do you, like I, have a collection of old DOS games lying around doing nothing?  Well, DosBox can help you run them again, on Windows XP. Relive those old memories… Civ, King’s Quest, Tetris… oh yes.

10. Pidgin – An IM chat replacement that works with Yahoo, Aim, and Google chat (you can use your GMail account as a username!)

11. Notepad++ – What can you do without a robust file editor?  Notepad++ can search, edit, replace, all the things you need in an editor.  It has context formatting for many file formats and best of all, it’s free!

12. TrueCrypt – Need encrypted containers to store your files?  Need to encrypt your system drive in-place?  Look no further than this amazing utility.

13. VLC Media Player – Great media player, along with Media Player Classic

14. Winamp – Still free, still out there, still my favorite.  You may need to uninstall the terribly cumbersome Yahoo toolbar after installing this package.  I’ve noticed Yahoo has slipped their toolbar into Java and a few other free packages too.  Shame on you.

15. CD Burner XP Pro – Despite the name, it is free software.  It works on Windows XP and Vista, but not so much on Windows Server.  You’re not burning discs on Server anyway, are you?  I also use Alex Feinman’s ISO Recorder.

16. OpenOffice.org – What free software list would be complete without it?  Although, I admit, I don’t use it much since I have MS Office.

17. Audacity – The best free audio recorder and editor I know of.  It has a nice interface and is all around easy to use.

What are some of your favorite free windows tools?  Leave a comment.

Taming the Beast

This blog is about Technology.

There are many times I want to write down experiences I’ve had; sometimes to remember what I’ve learned so that I gather a set of common solutions to common problems.  Other times, I want to share my experiences so that others can learn.

In truth, technology is a behemoth, an ever-changing monster, and we are locked in a struggle with it as new technology emerges and we try to master it.  IT people are intimately familiar with the constant battle to keep pace as people find new and exciting ways to use technology.  My philosophy is simple:  Technology can be good or bad.  It gets complicated when you ask, when does technology go bad?  And why?  And how the heck to fix it when it does?

I will attempt to provide you, the reader, with informative and entertaining posts about how to make technology work for you, and provide tips to bail you out when good technology goes bad.