undelete a just deleted file on ext4 with extundelete

Question

Is there a simple option on extundelete how I can try to undelete a file called /var/tmp/test.iso that I just deleded?

(it is not so important that I would start to remount the drive read-only or such things. I can also just re-download that file again)

I am looking for a simple command whith that I could try if I manage to fast-recover it.

I know, it is possible with remounting the drive in read-only: (see How do I simply recover the only file on an empty disk just deleted?)

But is this also possible somehow on the still mounted disk?

Answer 1

Looking at the usage guide on extundelete it seems as though you're limited to undeleting files to a few ways.

Restoring all

extundelete is designed to undelete files from an unmounted partition to a separate (mounted) partition. extundelete will restore any files it finds to a subdirectory of the current directory named “RECOVERED_FILES”. To run the program, type “extundelete --help” to see various options available to you.

Typical usage to restore all deleted files from a partition looks like this:

    $ extundelete /dev/sda4 --restore-all

Restoring a single file

In addition to this method highlighted in the command line usage:

--restore-file path/to/deleted/file
    Attemps to restore the file which was deleted at the given filename, 
    called as "--restore-file dirname/filename".

So you should be able to accomplish what you want doing this:

$ extundelete --restore-file /var/tmp/test.iso /dev/sda4

NOTE: In both cases you need to know the device, /dev/sda4 to perform this command. You'll have to remount the filesystem as readonly. This is one of the conditions of using extundelete and there isn't any way around this.

Answer 2

Typical usage scenario when undeleting all files includes need to restore all files deleted from /dev/sdX1 during approximately last hour:

mount -o remount,ro /dev/sdX1
extundelete --restore-all --after $(date -d "-2 hours" +%s) /dev/sdX1
find RECOVERED_FILES/

If satisfied with recovered files:

mount -o remount,rw /dev/sdX1

Answer 3

Unix isn't DOS. You can't make arbitrary modifications to filesystem data on read-write mounted partitions.

This is a Good Thing.

extundelete is a utility that can recover deleted files from an ext3 or ext4 partition. The ext3 and ext4 file systems are the most common default file systems in Linux distributions like Mint, Mageia, or Ubuntu. extundelete uses information stored in the partition's journal to attempt to recover a file that has been deleted from the partition. There is no guarantee that any particular file will be able to be undeleted, so always try to have a good backup system in place, or at least put one in place after recovering your files!