"Foreign" drive formats and "dd" command

[geebee2000]

I would appreciate some advice from someone who's already "been there, done that" with my situation. (Disclaimer: I am familiar with computers, but a TOTAL newbie to Linux/Knoppix!)

MY SITUATION:
I have two 160 Gb drives. I need to move the data from one drive to the other. I want to copy EVERYTHING from the "old" drive onto the "new" drive, including boot record info, etc. (I believe this would be called a "sector-by-sector" copy). The drives are from a ReplayTV unit (similar to a Tivo), and therefore have a proprietary drive format and operating system on them, which Knoppix does not seem to recognize (I've tried it a couple times.)

My current plan is to connect the drives with one as Primary IDE Master (jumpered as Master on the drive), and one as Secondary IDE Slave (or possibly Primary IDE Slave), again with the drive jumpered to Slave. My CD drive is IDE, and is currently running as Secondary IDE Master. I don't know if it can be rejumpered to be a Slave, and I don't know if it would work properly even if I WERE able to jumper it as a Slave. (Obviously, I need to have the CD working in order to run Knoppix off the CD.) I'd rather not mess with rejumpering the CD, but I will if it proves necessary.

QUESTIONS:
(1) Is it true that the Knoppix "dd" command will accomplish the transfer I am looking for, even if Knoppix cannot "mount" the drives?

(2) If so, are there any special parameters I should use in the "dd" command? My current plan is to open a Root window, and type in:
"dd if=\dev\hda of=\dev\hdb" (assuming that "hda" is the source drive and "hdb" is the target.) Do I need to worry about specifying any partitions, since I want ALL partitions copied to the "new" drive?

(3) Are there any limitations within Knoppix as to the size of the drive that can be handled this way? (I have installed an add-in IDE controller with a BIOS extension to permit my system to recognize drives over 137 GB, and the controller shows in the boot-up screen that it DOES recognize the drives, at their correct capacity.)

(4) How can I identify which drive is which from within Knoppix? (i.e. verify that my "old" drive is actually "hda", etc.) One drive will have a lot of data on it and one won't, but I don't know if there's any way for Knoppix to know how much data is on a drive, given that Knoppix can't read the formatting! Would Knoppix's FDISK command return any identifying information, such as the drive's serial number? Are there any other utilities that might help me figure out which is which? (I am reluctant to trust that the Primary IDE Master will be "hda"; should I not be so suspicious?)

Thanks for your help,
George

[eadz]

1) yes
2) no
3) I'm not sure, i don't think so.
4) hdparm -I /dev/hda will give you the serial number, along with other info.

[rickenbacherus]

(2) If so, are there any special parameters I should use in the "dd" command? My current plan is to open a Root window, and type in:
"dd if=\dev\hda of=\dev\hdb" (assuming that "hda" is the source drive and "hdb" is the target.) Do I need to worry about specifying any partitions, since I want ALL partitions copied to the "new" drive?

That will never work-look at your syntax-it seems very DOS like but this should work for you:
cat /dev/hda > /dev/hdb

It works quite well this way.

/dev/hda= primary master
/dev/hdb= primary slave
/dev/hdc= secondary master
/dev/hdd= secondary slave

Believe it.

I don't know if it can be rejumpered to be a Slave

Sure it can unless it's one of those drives from the outer edge of the galaxy. The primary channel can have one master and one slave. The secondary channel is the same. It doesn't matter which drive is which- for windows compatibility I would leave your windows drive on hda because it will throw a fit about not being on the first drive ( we should have suspected something was up with Bill from day one).

[eadz]

(2) If so, are there any special parameters I should use in the "dd" command? My current plan is to open a Root window, and type in:
"dd if=\dev\hda of=\dev\hdb" (assuming that "hda" is the source drive and "hdb" is the target.) Do I need to worry about specifying any partitions, since I want ALL partitions copied to the "new" drive?

That will never work-look at your syntax-it seems very DOS like but this should work for you:
cat /dev/hda > /dev/hdb

It works quite well this way.

What's wrong with dd if=\dev\hda of=\dev\hdb ?

[rickenbacherus]

What's wrong with dd if=\dev\hda of=\dev\hdb ?

dd if=/dev/hda of=/dev/hdb

[eadz]

What's wrong with dd if=\dev\hda of=\dev\hdb ?

dd if=/dev/hda of=/dev/hdb

Lol. I missed that!

[rickenbacherus]

Lol. I missed that!

I spent an hour the other night getting video to work. I reseated the card, checked cables, reset the CMOS & NVRAM still nothing- then I checked the power button. It seems that some monitors must actually be ON in order to function.

[aay]

What's wrong with dd if=\dev\hda of=\dev\hdb ?

dd if=/dev/hda of=/dev/hdb

Wow that's scarry. I missed that too. Quite right rickenbacherus - dos like.

[aay]

With regards to this issue I just found a new tool rescuing data on drives that have gone down..

ddrescue

What sounds nice about this tool is this:

Copying this partition with normal Un*x tools like cat or dd will fail, as those tools abort on error. dd_rescue instead will try to read and if it fails, it will go on with the next sectors. The output file naturally will have holes in it, of course. You can write a log file, to see, where all these errors are located.

At least this way you can get some (most?) of your data back even if you can't get all of it.

It has also just been put into unstable.

[geebee2000]

I guess my DOS/Windows ancestry is showing its scaly self!

I think I have the right "slant" on things now! Thanks for the help, everyone. I'll report back on how it goes. And I'll give "ddrescue" a try as well.

GB