ddrescue cloning disk to disk. I cannot see anything in the new disk why?

Hi Everyone,

I have a failing disk 1TB which does a bit of noise so I decide to use ddrescue to clone disk to disk the failing disk into a new WD 1TB.
I was expecting to see information in the new disk while cloning but i cannot see anything at all in it. It looks empty, in fact the cloning process stopped because i moved the old disk and I checked if there was something in the new disk and there was nothing!!! Why, what is happening? I continued the cloning again using the log file. The cloning goes very slow in 24 hours just 25GB has been cloned, but I cannot see anything in the new disk.

In the past when I created an image instead of cloning I could see how the image file was growing and even if I finished the creation of the image half way I could get info from the image.

What is happening? I dont want to be cloning a disk for 2 months a no info being stored in the new disk

Thanks so much in advance

Welcome to the forum.

1.) You would do best to write to an image if you have a drive large enough to store it. (can use sparse filing to save some space)
2.) Writing a bit for bit copy to the disk is not like writing a file. Once the partition table is laid, anything and everything can be data. until the disk has been written to and completed you may only see an ā€œemptyā€ partition.

Basically, lwt the copy finish and check on it later. if DD rescue is taking that long, that means that the source disk has serious issues. you can adjust the initial block size which should speed things up. Adding conv=noerror to the dd command will let it continue on errors and just write 0s in their place. then the ddrescue will use the log to try and recover areas where errors were concerned.

Thanks so much for your answer Mastlc_Warrior!

Let me see if I understand.
In the past when I created an image from a damage disk of 1TB after 10 days I decided to stop the process because it was taking too long. The image created was 175GB , it was not the complete image of the disk BUT with photorec i was able to recover from the image more than 100GB worth of pictures, videos and documents., even though the image was less than half way.

Now instead of a image i am cloning a disk to a disk because I dont have a third disk.
So my question is: if the cloning is not completed since it can take 2 o 3 months at this rate, will i be able to see any recovered information? if so how? or will I loose months since if it is not completed nothing can be recovered?
By now 60GB have been cloned (it is quite a lot of information) I would like to stop the process and check what has been recovered, can I do that? I can continue the cloning process with the log file that is not a problemā€¦

With images you can do that!!

It seems no many people knows about ddrescue cloning disk to diskā€¦ you are the only one who answered!!

Thanks in advance

@libelula

If you want to do a quick and dirty check, I recommend just doing a dd with bs=4096 conv=noerror. That will set block size to 4096KiB and if it runs into an error, then it will skip the block and write 0s to the target drive in place. You should be able to clone the drive in an hour or two. You can then mount the drive and see if you have anything useful.

he Default bs of dd is 512KiB I think. If your source drive has a lot of bad blocks or sectors, with ddrescue it will read from the beginning of the drive and work its way to the end. When it encounters an error, it writes it to the log. Then after the first pass, it will work its way from front to back on each error encountered. Each time making the bs read size smaller. At some point, when it cannot read a block, it will then start working from the end of the bad block encountered until it runs into an issue and then start making the bs smaller until it cannot recover data. It will do this for each original encounter. That may be why it is taking so long to finish.

The original mentioned solution with let you see just how bad your disk is and if it is even worth your time. May be easier to send off to data recovery solution.

With image files, they are files. FIFO applies. For disks, they are ā€œreadā€ as files but there is a lot of low level stuff going on that depends on disk physical structure. FS, and other things that just cannot be over come. You are right though, if the partition table is intact, you should be able to see how much of the data ā€œconsumesā€ the disk. You just may not be able to read any logical information on the disk until a significant portion of the disk (image/copy) has been written. Now is the best time to get an archive drive like an SSD. I have had too many archive HDDs die on me to trust them any more. All of my backup and archive drives are crucial 1TiB and 2TiB drives due to the read-only on failure mode that they support. You have less of a chance of losing the data on the drive.

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Thanks so much masterlc_warrior!!!

I am into a bigger problem!!! ā€¦
I stopped the process and I added the parameter -n --no scraping to make the cloning fasterā€¦ I left it over and in the morning linux mint was kind of blocked, desktop and bars had dissapeared, just the terminal goingā€¦ I decided to stop the process and restart linux mint!!!

Oh my god!!

When it restarted:
error: attempt to read or write outside of partition
Entering rescue mode
Grub rescue>

I tried few things on internet but didnā€™t workā€¦
So i have done a live usbā€¦
I can see 2 devices in /mediaā€¦ one Acer whic is my windows partition and i can access to all the filesā€¦ Great!!!

The second partition is the linux one 76GB having a large name b7f22c6d-85c1-445a-83f6 and same more numbers and laterā€¦
In the terminal when I get into this folder and I do a > ls it shows:

ls: cannot access ā€˜homeā€™: Structure needs cleaning
ls: cannot access ā€˜bootā€™: Structure needs cleaning

And the same for the folder opt, etc, lib64, mnt, usr,cdrom

I can access media, dev, lib

How can i repair the boot?
How can I repair the system and access to home folder?

You probably need to perform an FSCK to fix the journal, but I am afraid that that may cause you issues if that was your failing disk. Was the GNU/Linux drive your source disk?

Noooo that was not my failing diskā€¦ both the failing disk and the new disk were external disksā€¦ i was just using my internal disk (where linux and windows are) to save the logfileā€¦ i dont know what happened with the logfile to produce thisā€¦

So what i should do is just FSCK in my internal disk on the terminal? any parameters? will this fix the grub?

You will want to use a live distro as FSCK an EXT4 drive is still too new for me to trust it yet. just fsck.ext4 /dev/. I believe Fedora compiles with interactive on so just read the different prompts and answer accordingly. Adding the -f will force the fix flag, but you may not want to do that.

I am honestly not familiar with what the no scraping flag actually does besides state to not waste time looking over bad blocks on the first pass. Other than that, it should not affect your OS drive at all.

In regards to fixing grub, no, but you may be out of disk space due to the ddrescue log writing too much data ()source drive may have been really foobared).

I ran sudo fsck /dev/sda it says

/dev/sda is in use
e2fsck: cannot continue, aborting

I tried umount /dev/sda
and it says /dev/sda not mounted.

I just restart the system from a live usb so /dev/sda shouldnā€™t be in used ā€¦

what to do now?

you have to run fsck on a partition. so for example fsck /dev/sda1. So which ever partition has your directories that boot complains about, run it on that.

yes It worked ā€¦ it is sd5!!! fsck is running lets see what comes outā€¦

thanks so so so much!!!

No problem Heading home so will be away from forvm for a little bit. good Luck!

Mastic_warrior, I ran many times fsckā€¦ it starts great and then aborts ā€¦e2fsck aborted!
I ran it many times but it does fix some errors and aborts again.
it seems like the access to /home /boot is locked
What else I can doā€¦ to be honest I want to access to /home folder to save all the info i had thereā€¦ if i cant recover the system ā€¦ well i will install linux mint again (i hope this is possible) but i dont want to loose the info i had there!

What to do now?
Thanks so much for your help

Oh wellā€¦ I decided to run fsck again

fsck -y /dev/sda5

It aborted and I ran it againā€¦ like that 6 times and finally it finished it without aborting!!
I thought it was great but oh my god!!

fsck deleted all the folders that were locked and could access to it, therefore /home /boot /opt /etc /lib64 /mnt /usr /cdrom folders have been deletedā€¦ I had 34GB free in that partition ā€¦ now I have 61GBā€¦ what do i do to recover my /home folder?
I am guessing with those folder missing my linux system is gone!!

It would take some work, but you may be able to restore the journal if you are using a journaling file system. If you are using an HDD, then you may have better luck. You would need to look that one up though. I has been decades since I have tried to perform that kind of surgery.

backtrack 5, kali linux, are 2 very good forensic distros that may help you.
you may be able to save the home directory itself but thats to be seen in trying.
rescatux may help as its designed for rescuing linux systems.

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