Monday, December 14, 2009

Backups that just work.

After all the drama with the KSODs that I experienced in Vista and Win7, I’ve decided that it is high time that I put together a good backup system. Here’s what I’ve come up with.

I have a primary backup system that continuously backs up data, and a secondary system that images the computer every other week.

My primary backup program is called Rebit. The company tagline for the product is “Ridiculously Simple Backup” and for the most part, this is true.

Rebit is a bit like Time Machine on the Mac, sans the cheesy user interface, working quietly in the background using the Microsoft Volume Shadow Copy Service to backup everything to the Rebit appliance.

The software supports revisioning, so you can back up and access multiple versions of files like you can in Time Machine.

There are virtually no settings to configure – it just backs up everything -which adds to its simplicity. However, this can be a little frustrating to techies who want to be able to verify backups or apply backup filters to exclude large VMware images, for example.

So far, everything has worked smoothly with the 1TB Seagate Desk external USB hard drive that I bought for the Rebit. The installation and activation of the software went smoothly, and creating the first system image took overnight.

Subsequent incremental backups took much less time. If Rebit is plugged in, it seems to echo file changes pretty quickly, but also creates a new incremental system image daily. If it is not plugged in, Rebit automatically will catch up with all the file changes the next time you plug it in.

My secondary backup program is Paragon Backup & Recovery 10 Free Edition. Paragon Backup is free for personal use.

I was very pleasantly surprised by how full featured it is for free software, supporting archive verification, boot USB & CD creation and even incremental backups. 

I use this program to create a drive image every other week.

I should mention that both Rebit and Paragon Backup are compatible with Win7 64-bit. I haven’t tried to restore from a backup from either system yet, but will report back when I do.

Incidentally, Rebit for some reason just would not work with an older 640MB Western Digital Caviar Blue hard drive that I had put in two different USB enclosures. At random times it would freeze the computer which wouldn’t recover until I turned off the external drive.

However, the WD HD is working fine as a Time Machine drive in Meike’s Mac Pro. Perhaps it likes Macs better.

Tuesday, December 8, 2009

ImageJ “Import Using QuickTime” requires 32-bit Java & QTJava.zip.

The open source image analysis program ImageJ by the National Institutes of Health is a fantastic free tool for scientific imaging. It can do cool stuff such as this.

However, I’ve discovered that it natively supports only the AVI 1 specifications which limit your video imports to 1GB, even when using virtual stacks to open larger files.

The workaround I found was to import the video using the “Import Using QuickTime” feature under File > Import > Using QuickTime.

Unfortunately, this add-in doesn’t work when called from a 64-bit Java environment. So I reinstalled the 32-bit version of ImageJ.

It still didn’t work. I finally tracked it down to some instructions that I had missed here.

Basically, the fix involves copying the QTJava.zip file from “Program Files (x86)\QuickTime\QTSystem\” to “Program Files (x86)\ImageJ\plugins\Other-Plugins\” which did the trick.

I don’t recall doing this previously before I switched over to a 64-bit OS, but this procedure fixed my installation and I can happily open large video files once again.

Monday, December 7, 2009

Windows 7 Backup fails with 0x8100033.

Quick note: I have been having problems with the Windows 7 Backup program creating a system image. It always fails with 0x81000033 error, and a quick search on the Internet reveals that other people are having the same problem too.

The most common theory is that the hidden System Reserved partition installed by default with Win7 has too much “data” in it, causing the Microsoft Volume Shadow Copy Service to fault out because it does not have enough working space on that volume.

Sneha, the Microsoft representative in this thread on social.technet.microsoft.com believes the problem is due to the USN journal setting for the partition being changed by third-party software, eating up space on the hidden volume and causing Backup to fail. Backup requires

The last post by Sneha in this thread was only 19 hours ago and unfortunately he doesn’t have a solution other than to turn off the system image option in Backup. This is an unacceptable solution.

Hopefully, Sneha will return with a definitive solution on how to fix this. As of now, I still have no good backup solution, but I will try to reinstall Rebit on my new external hard drive, since I could never get it to work with my old HD.

Side-note: If Sneha’s theory is correct, could Rebit have changed the journaling settings for the System Reserved partition? I have been able to perform a system image backup successfully with Windows Backup *once*, and this was before I installed Rebit. Hmmm…

EDIT: I found this solution on the web. I haven’t tried it myself, but it seems reasonable. Just make sure to backup your system first before messing around with the System Reserved partition:

Thread Title w7x64rc backup fails with error code 0x81000019
Started by: david.wells

Reply: A Workaround Without Repartitioning:

When trying to make a system image of Windows 7, I got error 0x80780119.  After searching this thread (plus others), I found my 100 MB System Reserved partition had grown a large USN journal.  I assigned it a drive letter.


Fsutil usn queryjournal F:

Then I ran this command to clear and disable the USN journal on my System Reserved partition:

fsutil usn deletejournal /N /D F:

This freed 48 MB.  The USN journal on my System Reserved partition remained disabled after a reboot, which I verified by re-running the query.  Subsequently, I was able to make a system image without error.

Look here for details on FSUtil: http://technet.microsoft.com/en-us/library/cc788042(WS.10).aspx

Mancer, MCITP-EA

Thursday, December 3, 2009

Seven Excel 2007 tricks and tips for data analysis.

When taking data for simple scientific experiments, typically you have built in replication so that you can calculate the means, standard deviations and the 95% confidence intervals at each setting of interest.

But it’s always such a pain to massage the format and order of the replicated data so that you can perform the statistical magic.

Here are some Excel tricks and tips that help me when I perform data analysis. You can find more information in Help or on the Web:

  • Sort: The sort function in Excel is your friend. Use it to sort the data in numeric order from smallest to largest.
  • Consolidate: This magical Excel function takes a list of data with replication and outputs lists of averages and standard deviations for each unique variable in the left-most selection column of the Reference area. From these, you can calculate the 95% CI with ease and plot the data with error bars.
  • SHIFT + END + RIGHT and SHIFT + END + DOWN: These two key sequences select cells from your cursor to the right-most-end and bottom-most-end of your data block respectively. It is so much more efficient than click-dragging down through pages and pages of data.
  • DOUBLE CLICK the Fill Handle: This auto-fills a formula down to the bottom of the list, referencing the size of the column to the left of the formula – no need to click-drag this either. The Fill Handle is the black dot at the bottom right of the cell.
  • F4 toggle: This toggles the cell reference between a relative reference that moves with the cell and an absolute one that stays fixed (the cell reference has the dollar signs in the address).
  • VLOOKUP: This command allows you to find values using a lookup table. Use this to code/decode your data or to calculate the value of a function using a lookup table approximation.
  • Error Bars Add-In: This free third-party add-in from Jon Peltier allows you to set error bars in both x and y directions easily from a single dialog box. You can set this to the 95% CI column to add meaningful error bars on your graphs.

Excel is a wonderful tool for analyzing simple experimental designs. For more more complicated experiments including DOEs, Response Surface Analyses, I would recommend using a statistical package like Minitab, SigmaPlot or the Statistics Toolbox in Matlab.