boot options? access from Win?

Forum: USB booting
Topic: boot options? access from Win?
started by: 9a6or

Posted by 9a6or on May 22 2005,20:33

I've installed DSL 1.1 onto a Sandisc Titanium 512MB using the USBHDD method.
DSL boots well but I have no chance to enter any boot options (that might be needed on different PCs).
The other problem is that the partition is not accessible from Windows ie. cannot be used to transfer files (one of the main functions of a USB stick).

Previous versions did not have these limitations.

Posted by roberts on May 23 2005,08:27

The USBHDD script make a Linux (ext2) partition.
Now, I am no Windows expert, but I don't think Windows can read/write Linux without some special software.

No boot options is just like the hard drive install version.

It is the syslinux version, USBZIP, that emulates a floppy and has boot time options. The issue with this is that cdertain geometry is required in order to make it boot.

Posted by 9a6or on May 23 2005,15:16

In the meantime I tried out the USBZIP method and the 50MB partition (FAT) is seen by Windows, and the boot options are also available. Is there any way to increase the size of the first partition? Potentially to occupy the full capacity of the USB stick? In that case the usability of the USB stick would be maximised (access to boot options and usability in Windows).

Posted by roberts on May 23 2005,15:49

I will share with you the limits of my knowledge and experience on this matter.
The USBHDD is simple, it seems to work no matter the size of the pendrive. However, it is limited to BIOS that can boot USBHDD and windows cannot see it. Therefore it is not suitable for running dsl-embedded, i.e, qemu.

USBZIP is a pain because of the geometry required. The latest version of Syslinux contains an executeable that I call from my install script, frugal_usb.sh. The executable is mkdiskimage. The line in the script is: ./mkdiskimage -1 /dev/$DEVICE 50 64 32
The 50 is for the 50MB partition. I don't have large pendrives to test, so I asked Kent, ke4nt, to help me test my script. What we found is that the executeable fails at larger than 250MB. Now, when you come to think of it, the zip drives were 250MB. So, if you pendrive is 256MB or less you might be successful by adjusting the 50 to 120 for 128MB or 250 for 256MB. Another adjustment, is to change the 50 to 0 the executeable will try to calculate the geometry needed for your pendrive. Again it fails on anything larger than 256MB pendrive. Actually, my first attempt at creating my script, I used the zero option and only a single partition, hoping it would work on all pendrive size. Unfornately not. I still have my original script. I could post it but again it will fail with anything larger than 256MB pendrive.

Note that if you make that adjustment to the script, the script is still trying to make a 2nd partition and pre-setup the restore and mydsl to use the second partition.

My point being is that you lose very little by having two partitions. I must write code to handle the widest number of cases. I cannot enjoy the "well it works for me" syndrome.

But, I do see your point, you want to maximize that area of which windows can see. I guess that being, is becasue you download using windows and not linux?
Or is it qemu that is your desire?

Posted by 9a6or on May 23 2005,20:24

Thanks for your thoughts.

I gues I am in the usual position of the Linux curious who is surrounded by Windows PCs at work. I am using the advanced features of Word, Powerpoint, Excel when communicating with colleagues/students and unfortunately AbiWord/OpenOffice cannot fully read/write my files. For this simple and unavoidable reason I have to continue using Windows including read/write to the USB stick's FAT partition.

I will try to modify your script and get it to create a 250MB FAT partition (visible to Windows) and reserve the rest (262MB) for DSL.