does "tohd=/dev/xxx" copy just the files from the KNOPPIX directory?

[knopvm]

i'm asking this more from curiosity than anything else, but i haven't found anything in the FAQ or forum yet that explains the details of what "tohd=" does; if anybody can answer my question in a second or two, i would appreciate it. if not, no answer is OK, too.

i finally bought a new laptop last year. it has a 931GiB disk, which had Win10 installed on it; i don't use it very often (mostly just to get Win10 updates), so i booted from my USB knoppix 7.6 drive, shrank the Win10 partition down to a 146GiB, and put the remaining 773GiB into a new partition, on which i created an ext4 filesystem. i then rebooted using the "fromhd=" parameter, and everything works fine. my intention is to either boot into Win10 or (more likely) use a knoppix USB drive to boot into knoppix using the "fromhd=" parameter. i later booted from the USB drive again, and it would appear that the only files that "tohd=" put onto the partition were the ones found in the KNOPPIX directory on the USB drive.

i only recently started making extensive use of the laptop, because the job i used to have was 24/7/365, and i didn't get much rest, let alone time to mess with the machine. now that i can play around, i have begun storing files on the ext4 partition, but it occurred to me that if "tohd=" re-images the partition the way flash-knoppix does, having data stored on the same partition isn't a good idea. if, OTOH, i can just copy the files from the USB drive (or loop-mount the latest ISO and copy from that), i'm OK where i'm at.

any quick explanation of "tohd=?"

[joselb]

In my case, I used "tohd=/dev/sda2 mkimage" booting from my knoppix pendrive to copy knoppix to the internal hard drive (it only creates a normal folder named KNOPPIX). My data and changes are always encrypted with a password (AES256) and when I boot with the pendrive it searches for this folder automatically, I don't need to use the cheatcode "fromhd". When I type rhe password after knoopix asks me to use the encrypted data then I can continue without the pendrive. If I want to boot only from the pendrive (not from the folder of the hard drive) then I need to use "fromhd=/dev/sdb1" and so it avoids the harddrive. You don't need nothing more or format anything. It creates a folder inside your Windows o.s. and boots from there.

[knopvm]

thanks, joselb.

when i originally did the "tohd=," i didn't use mkimage with it. now that U have mentioned it, that brings up another question. am i correct in assuming that the mkimage cheatcode generates the overlay file? i have never used it, so i don't know.

since my original post, i bit the bullet, backed up all the files i had on the ext4 partition (Just In Case), and copied all the files from the KNOPPIX folder of the 7.7.1 .ISO to the partition (after re-naming the original directory put there by "tohd=" from my 7.6 USB flash drive ... also Just In Case). i then re-flashed the drive with flash-knoppix and booted the system, and all is good.

when i was using knoppix 7.2 (on other people's borrowed computers), i used an aes-encrypted overlay, but the flash drive bit the dust, and i lost everything (i know, i should have backed it up ... but i didn't). when i got this computer, i decided to use other ways to obfuscate and encrypt the stuff i want to keep private instead of an overlay file. what i have now is therefore not standard, but it works, and is *exactly* what i want.

again, thank U for the help!

[fredvej]

Yes, tohd=/dev/sda2 copies the KNOPPIX directory from your boot medium to the root of the partition /dev/sda2. It does not copy minirt.gz and the kernels linux and linux64 from bootmedium/boot/isolinux , so you cannot boot Knoppix using only the copied KNOPPIX directory.

What do you want to do ?

If you do not want to mess with your Windows boot partition, you can boot from your USB stick and use the cheatcode fromhd=/dev/sda2 to use the /KNOPPIX files on the hard disk. This will boot Knoppix, and once it is up and running you can remove the USB stick. There is no persistent storage, so when you e.g. change settings, they will disappear when you shut down.

If you want to use your ext4 partition (guessing it's /dev/sda3) as persistent storage for Knoppix, you must create a file /dev/sda2/KNOPPIX/knoppix-data.inf with this content:

3 /KNOPPIX-DATA ext4

This tells Knoppix to mount partition 3 on this hard disk on mountpoint /KNOPPIX-DATA as an ext4 file system.

The next time you boot from your USB stick and use the cheatcode fromhd=/dev/sda2, Knoppix will use /dev/sda3 as persistent storage and create directories /etc , /home , /root , and /var to be used for saving settings and /home/knoppix . This does NOT delete anything that is already on /dev/sda3 , so what you have stored there will not be touched.

[knopvm]

thank, fredvej, but i boot from my USB stick, and i haven't used persistent storage in a long time. i copied the files from the KNOPPIX folder to the ext4 partition and flashed the USB stick to the same revision, then played some games and got everything where i want it. however, i appreciate learning about the way things work, so thank U for explaining about knoppix-data.inf and the way persistent storage works.

[knopvm]

OK, i have to admit that i'm forum-challenged; i posted a response to both joselb and fredvej, but neither got through. i'm so confused!

actually, all is well now, but i appreciate the responses of both of U. as usual, when one RsTFM ("Reads" TFM) and doesn't find an answer, asking others almost always helps.

anyhow, before i got any answers, i ended up backing up all the files i had on the ext4 partition, then copying the contents of the KNOPPIX folder from the .ISO for 7.7.1 to the partition, flashing the USB thumb drive to 7.7.1, and rebooting. as U folks intimated, all went well, and i'm back up with a later version.

again, thank U very much!