Making a USB boootable from an ISO file

• Prepare a bootable USB by using RMPrep with grub4dos.
• Download an ISO file, e.g. Panda Safe CD ISO, "SafeCD.iso" 
• Mount that iso so we can view and access all files in that iso.
• Notice the dir structure in the iso. It should have a file call "isolinux.cfg". Look inside "isolinux.cfg" with text editor, It should mention a file that show up a menu upon starting up the iso. In this example, the file is called "menu.cfg".
• Look inside "menu.cfg" with text editor. It should show the detail of the menu. Here is:

LABEL live
    MENU LABEL Start SafeDisk
    kernel /live/vmlinuz1
    append initrd=/live/initrd1.img boot=live union=aufs



Here we have to adjust this accordingly to our menu.lst. This can be shown as


title Panda Safe CD
find --set-root /live/initrd1.img
kernel /live/vmlinuz1 boot=live union=aufs
initrd /live/initrd1.img

Notice all necessary files are in one directory. Here is directory called "live". Copy the whole "live" directory to our USB. Then put a new created menu.lst into the root of our USB.

Booting USB from Virtual Box

VirtualBox can be set to accept booting from USB. This is purposed to test the recovery USB stick. Instead of booting from the real machine, you can boot the USB recovery stick from the virtual machine so it is easier to fix the USB. This is very useful for making a booting USB like in my earlier post, "Multiboot USB with 15 instances".

There are 2 methods to boot the USB in virtualbox. First, we can use PloP as an ISO image to attach to the CD ROM drive of any OS in the virtualbox. Then we add our real USB in the USB setting of Virtualbox. (Don't check Enable USB2 box because PloP doesn't support it.) When used, this USB will be seen by the Virtualbox OS only. This method can be used with any bootable USB. The problem is that it is very slow to boot an OS in the USB because PloP allows connecting with USB1 only.

The second method is creating virtual USB device from the real USB with this command:

VBoxManage internalcommands createrawvmdk -filename "%USERPROFILE%"\.VirtualBox\usb.vmdk -rawdisk \\.\PhysicalDrive#

where # is the USB disk number (looked in Windows Disk Management.). The virtual USB is usb.vmdk file. This can be added in Virtualbox as an existing hard drive.

Don't add our real USB in the Virtualbox USB setting as the USB needs to be seen from the host windows.

Note that this virtual USB will use with the USB that you created with only. The order of plugging the USB is also important. This has to be the order to make the USB the right PhysicalDrive number. It means if you fail to do this, i.e. changing from 8G to 4G or plugging the USB the wrong order, the system won't boot. Therefore, it is a good idea to name this Virtualbox OS to be something meaningful like "Virtual USB 8G Disk2". The advantage of this method is that the USB speed is much faster than the first one. This is the method of my choice.

Last but not least, you need to set Virtualbox base memory and video memory to some extent; otherwise, some OS won't boot up. I am using 2048M for the base memory, and 32M for the video memory.

"Could not load file or assembly MOM.Implementation..."

After I had installed the latest graphic drivers from ATI, every time I right-clicked on the desktop, and selected "Graphic properties", this annoying message

"Could not load file or assembly MOM.Implementation..."

showed up. The message itself caused little problem. However, the real problem was I could not adjust any graphic properties even with the basic settings like screen resolution and color depth, let alone other advanced features like 3D settings such as AA, AF, and so on. I can use my PC just fine but what is the point of installing a new driver if you cannot fully utilize its advanced features? So instead of let it be as it is, I was busy trying to make it work. It was painstaking but finally I managed to put this error away. Here is how I do it.

You will need 2 free, external helpers, DriverSweeper and CCleaner.

First, you'll do as you normally do: uninstall all the old ATI drivers with its own uninstaller in Control Panel/Uninstall of Windows. Unfortunately, this is not enough. The ATI uninstaller have a bad habit to leave many leftovers behind, and this causes the problems. So we need to do more cleaning. This can be done by using DriverSweeper. Open DriverSweeper, select ATI option and clean it. This will clean not only the ATI files but also the related branches in the registry. The last step, use CCleaner/Registry to clean more of the registry. Repeat CCleaner until it says there is nothing more to clean.

After all the cleaning is done, it is time to install the new ATI drivers. Restart your machine, and proceed to install them. The installation should go smoothly. Don't forget to check whether or not that annoying message is gone for good. I bet it will.

Renaming several files to a list of text names

There is a situation that you may want to rename several files to a list of text names. For example, you have a series of a TV show listed as

• A1.avi
  
• A2.avi
• A3.avi

and want to rename these files to

• AS01E01_Debut show.avi
• AS01E02_She is here.avi
• AS01E03_He is there.avi

You can see that the names we want to change to are not in any pattern. This is a problem for most auto-rename softwares, which needs at least some patterns of texts to replace some parts of the old names.

Fortunately, this problem can be solved easily with this tiny, free software called Text to File Renamer (V 2.1). It is very easy to use. First, you drag your files to the left panel. Second, you paste the list of the names you want to rename to the right. Then the final step, you just click the last button. It’s that simple!

One quick note, you may find another free program to complement this action. It is called Filemenu Tools. One of its commands can be used to copy only the file names of the selected files. If you want to change the names of one set of files with another set of the files, you can use this tool to copy the file names of the latter set, then paste it into the right panel of Text to File Renamer. Very very handy tool.

Note: For this kind of work, you can try a program call Renamer. (Yes, It is free too.) It is very powerful, which can do many many things about changing names. It is no doubt a first-rated utility, but you may need time to learn how to use it.

No sound transferred from a notebook to TV with HDMI connection

My notebook is Acer TimelineX 4820TG, Windows 7 64 with Realtek audio hardwares. It has a HDMI port, and I use it to connect to my plasma TV. It does its job beautifully transferring both video and sound with only one cable connection. Recently, I found that many times the sound didn't come out from the TV speakers. The pictures from my notebook came out to TV ok but not for the sound. After spending hours of internet searching and trying, I finally managed to fix it. If you experience something like that, try this:

Go to Device Manager in Control Panel
Go to System Devices (not Sound, video and game controller branch as you might think) and look for High Definition Audio controller that marked with an arrow icon indicating this device is not working properly or is disable. Fix it there by updating the drivers or just enable it.


Now when you connect HDMI to TV, if it hasn't any sound on TV, go to a Sound setting in Control Panel (or you can go to a speaker icon on the tray, then right click it) and select Playback devices. Right there, you should see HDMI sound output. Select it and click Make Default.

Multiboot USB with 15 bootable instances (Updated)

OK. There are a lot of tutorials about how to make a multipleboot USB. Why do I have to make one myself? The answer is that most tutorials are very confusing and they won't explain the reason behind those instructions lines. Here is my own version. If you feel it is familiar, that's because I collect all these information from the internet.

Note this uses GRUB4DOS as a boot loader to load an OS, and there is no partitioning of USB involved. Obviously, this is an advantage over other methods. The USB size should be at least 8G.

Words of warning: The files in USB can be corrupted easily as you may be forced to shut down the system in case you cannot boot up the system as expected. I recommend to back up all the file in USB. If something used to work before, then suddenly goes wrong, just repeat step 1 and 2, and copy everything in the backup to the USB.

Tools: HP USB Disk Storage Format Tool 2.2.3, Syslinux, Grub4dos

Objectives: Making a USB bootable with 15 instances: DOS, Hiren Boot CD, Hiren Mini XP, UBCD for Win, Ubuntu, Part Magic, AVG, Kaspersky, Dr Web, Avira Antivir, MS Data recovery XP-Win7, WindowsKey and so on.

Step 1: Make a USB
Use HP utility to format the USB stick. Use this tool to format the USB stick because it will prepare the stick's boot sector properly just for the next step.

Step 2: Install SYSLINUX boot loader into the mbr of the USB, using command syslinux -m -a X: , which X is a USB drive. After install the syslinux bootloader, a file ldlinux.sys will be created in the root of USB. (Note that you may try using GRUB bootloader but I found using GRUB cause nonbooting with AVG rescue CD iso. See Update***)

Step 3: Copy GRUB shell into USB
GRUB shell is GRUB.EXE, we have to copy GRUB.EXE into the root of USB, then create a text file syslinux.cfg. Call GRUB.EXE with these lines in a syslinux.cfg file.

default grub
LABEL grub
KERNEL grub.exe

Now your USB root should have 3 files, ldlinux.sys, syslinux.cfg and grub.exe

(If you use GRUB bootloader, copy GRLDR into the root of USB instead of grub.exe.)


***UPDATE Step 2-3 Install New GRUB bootloader and GLDR
New grub4dos 0.4.5c (2013-01-13) has been released. I found it works really well. It can now boot the new Knoppix7 ISO, and does not have any issue with AVG ISO. After formatting the USB in Step 1, you can install grub bootloader and gldr to your USB in one step using RMPrepUSB (Set Partition size to MAX, Bootloader option to MSDOS, File system to FAT32/ Boot as HDD, and click Install Grub4Dos.) Note that RMPrepUSB has already included the new grub bootloader and glrdr in its package so you don't have to separately download the new grub again. Another way to install GRUB bootloader is to use BOOTLACE.COM included with grub4dos package. Use BOOTLACE.COM 0x80 to install the bootloader to disk0, use  BOOTLACE.COM 0x81 to install the bootloader to disk1, and so on. Check the disk number with MBRWIZ.

After this step, your USB should have only 1 file, glrdr.


Step4: Set the first boot, Windows98 MSDOS
Now we are ready for the first boot menu, windows98 DOS. Copy these files from win98 CD into the root of USB, MSDOS.SYS, IO.SYS and COMMAND.COM
Create a text menu file to call this boot stance by putting these lines into a text menu.lst file:

color white/blue black/light-gray
timeout 20
default 5

title Shut down
halt

title Reboot
reboot

title DOS Win98 Boot
rootnoverify (hd0,0)
chainloader /io.sys

The first 3 lines are for appearance's setting. Next two title entries are for power off and restart the machine.

The next lines can be explained as following:
title DOS Win98 Boot :The display boot menu.
rootnoverify (hd0,0) :Set the first hard disk (the USB stick itself in this case) and first partition as root without mounting disk.
chainloader /io.sys :Load io.sys in the root to boot.

After reboot with this USB, you should get this screen.

Step 5: Set Hiren Boot CD, Hiren Mini XP
Copy HBCD folder in a Hiren Boot CD into the root of USB drive. Note that we do not boot Hiren from the ISO, but we boot it from its boot file. Add the following lines in the menu.lst file:

title Hiren Boot CD 10.4\nRun Dos Programs
find --set-root /HBCD/boot.gz
kernel /HBCD/memdisk
initrd /HBCD/boot.gz

title Mini Windows Xp (50 sec)\nRun Antivirus and other windows programs
find --set-root /HBCD/XPLOADER.BIN
chainloader /HBCD/XPLOADER.BIN

Step6: Set UBCD for Windows
We need another USB drive. Create UBCD4Win with UBUSB.EXE to the new USB drive. Then copy the following files and folders from the UBCD4Win USB to our USB:

Folders: UBCDW, MININT, PROGRAMS
Files: ntdetect.com, ntldr, win51ip, win51ip.sp2

Add the following lines to our menu.lst:

title Launch "The Ultimate Boot CD for Windows"
fallback 1
find --set-root /ntldr
chainloader /ntldr
savedefault --wait=2

Step 7: Set UBuntu
Create a folder for UBUNTU e.g. ubuntu1010 in the root of USB drive, and extract 6 following files-- filesystem.manifest, filesystem.manifest-desktop, filesystem.size, file system.squashfs, initrd.lz and vmlinuz from UBUNTU iso CD into this folder.

Add the following lines in menu.lst

#This is for a space
title
root

title Ubuntu 10.10 LiveCD (30 sec)
find --set-root /ubuntu1010/initrd.lz
kernel /ubuntu1010/vmlinuz boot=casper live-media-path=/ubuntu1010/ ignore_uuid
initrd /ubuntu1010/initrd.lz

Caution: Ubuntu 10.10 has a problem with directory named "sources". I don't know why. If your USB has a directory named "sources" anywhere in the USB, it won't load Ubuntu. Strange. At least, I'm glad I found why sometime I can't load Ubuntu. It has bugged me for long time.

Step 8: Set Parted Magic
Create a folder images in the root of USB drive, and copy partedmagic iso into this folder

Add the following lines in menu.lst

title Parted Magic 5.6 (50 sec)
find --set-root /images/pmagic-5.6.iso
map --heads=0 --sectors-per-track=0 /images/pmagic-5.6.iso (hd32)
map --hook
root (hd32)
chainloader (hd32)

Now you USB should have 2 G used, and 6 menus showing up in the USB root directory.



Step 9: Set AVG antivirus rescue CD (On/off line update)


Download AVG antivirus rescue CD and copy into images folder of our USB
Create avg-update directory for keeping the virus database. This is not a must, but it is good to have a specific directory for downloading virus definition.
Add the following lines in menu.lst

#This is for a space
title
root

title AVG Rescue CD (Anti-Virus + Anti-Spyware)
find --set-root /images/avg.iso
map /images/avg.iso (hd32)
map --hook
chainloader (hd32)

This antivirus rescue CD can be updated online/offline. To update it, select Update, then select Online, Offline or Download.

Step 10: Set KAPERKY RESCUE CD (On/off line update)

This rescue CD can be updated online inside the program or offline by downloading a new iso.
Rename "kav_rescue.iso" to rescue.iso, and put it in a newly created RESCUE folder
Create a zero file named liveusb in the root of USB.
Add the following lines in menu.lst

title Kaspersky Rescue CD (Virus Scanner)\nUpdated by downloading the new iso, rename it to rescue.iso, and replace the old iso in a rescue directory
find --set-root /rescue/rescue.iso
map /rescue/rescue.iso (0xff)
map --hook
root (0xff)
chainloader (0xff)

This program doesn't work on all systems, e.g. on some notebooks. Still don't know why.

Step 11: Set Dr WEB Live USB 
You will need an extra USB. Download DrWebLiveUSB.EXE and make a DrWebLiveUSB to this USB.
Copy the whole boot directory to the root of our USB
Add the following lines in menu.lst
Edit ID=xxxxxxxxxxxxxx as the same in isolinux.cfg (Text in the line starting with kernel as the same as in syslinux.cfg without ID=)

title Dr WEB CD (Virus Scanner)\nUpdated by downloading the new iso, and extract boot directory to the root of USB
find --set-root /boot/initrd
kernel /boot/vmlinuz ID=WfHmREDlRSXOT6wb root=/dev/ram0 init=/linuxrc init_opts=4 quiet dokeymap looptype=squashfs loop=/boot/module/white.mo usbroot slowusb vga=791 splash=silent,theme:drweb CONSOLE=/dev/tty1
initrd=/boot/initrd

Step 12: Set AVIRA AntiVir Live CD (Online update)

Prepare an extra USB.
Download avira rescue cd iso and make USB version by UnetBootin on the extra USB.
Copy 3 folders (avupdate, antivir, and system) from the extra USB to the root of our USB
Add the following lines in menu.lst

title AVira
find --set-root /avira/initrd.gz
kernel /avira/vmlinuz nofb ramdisk_size=108178 root=/dev/ram0 rw console=/dev/vc/4
initrd /avira/initrd.gz

This program can be updated online only.



Step 13 Add F-Secure (On/offline update)


Download F-secure rescue cd iso. Use UNetBootin to make a spared USB bootable. Copy boot/isolinux  and Knoppix directory in the root of our USB. Notice the text file, syslinux.cfg. It should have these lines of codes:

label ubnentry0
menu label rescuecd
kernel /boot/isolinux/fsecure/linux
append initrd=/boot/isolinux/fsecure/minirt.gz ramdisk_size=100000 lang=en vt.default_utf8=0 apm=power-off vga=normal quiet  nomce loglevel=1 nolapic_timer nosound console=tty10 video=noblank

Now we will adapt this code into grub4dos of our menu.lst as follows:

title F-Secure Rescue CD
find --set-root /boot/isolinux/fsecure/minirt.gz
kernel /boot/isolinux/fsecure/linux ramdisk_size=100000 lang=en vt.default_utf8=0 apm=power-off vga=normal quiet  nomce loglevel=1 nolapic_timer nosound console=tty10 video=noblank
initrd /boot/isolinux/fsecure/minirt.gz

If the system can connect to the internet, the virus database can be updated online. If not, it can be updated offline by put the virus database into the main root of the USB, downloaded from

http://download.f-secure.com/latest/fsdbupdate9-packed.run

Step 14 Add Panda Safe CD

 Download Panda SafeCD iso, then extract all files in directory "live" to a folder "panda" in your USB stick, then add these lines in "menu.lst".

title Panda Safe CD (20 sec)
find --set-root /panda/initrd1.img
kernel /panda/vmlinuz1 boot=live live-media-path=/panda/ ignore_uuid
initrd /panda/initrd1.img

Step 15 Add Bitdefender Live CD

Step 16 Add Knoppix Live CD

Step 17 Add
 

Incompressible and compressible flow

Have you ever been confused which one is compressible or incompressible flow in fluid dynamic course ? The importance of these flows is mentioned in the Bernoulli's equation, which stated that it is valid only with incompressible flow.

I used to think that compressible flow is the flow of gas, and incompressible flow is the flow of liquid. As everyone knows gas is compressible but liquid is incompressible, that's why I came up with that idea.

But I was wrong. It turns out that flow of gas could be incompressible flow too, and it is usually so!, because most flows are well below the speed of sound. That means Bernoulli's equation can be applied for both liquid and gas flows. Check this out from Wiki:

For flow of gases, to determine whether to use compressible or incompressible fluid dynamics, the Mach number of the flow is to be evaluated. As a rough guide, compressible effects can be ignored at Mach numbers below approximately 0.3. For liquids, whether the incompressible assumption is valid depends on the fluid properties (specifically the critical pressure and temperature of the fluid) and the flow conditions (how close to the critical pressure the actual flow pressure becomes).

So this is just a reminder, at least for myself.