filesystems Archives - Page 4 of 12

How are directories implemented in Unix filesystems?

August 10, 2022 by Magenaut

My question is how directories are implemented? I can believe a data structure like a variable e.g. table, array or similar. Since UNIX is Open Source I can look in the source what the program does when it created a new directory. Can you tell me where to look or elaborate on the topic? That a directory “is” a file I could understand and is a directory really a file? I’m not sure that it is true that files are stored “in” files while still in way you could say the word file about nearly anything and I’m not sure what absolutely not is a file since you could call even a variable a file. For example a link is certainly not a file and a link is like a directory but then this violates that a directory is a file?

Can’t resize a partition using resize2fs

August 10, 2022 by Magenaut

I recently resized the hard drive of a VM from 150 GB to 500 GB in VMWare ESXi. After doing this, I used Gparted to effectively resize the partition of this image. Now all I have to do is to resize the file system, since it still shows the old value (as you can see from the output of df -h):

What happens when you delete a hard link?

August 10, 2022 by Magenaut

If you do rm myFile where myFile is a hard link, what happens?

Mount device with r/w access to specific user

August 10, 2022 by Magenaut

How can I mount some device with read-write access for a given user?

What directories do I need to back up?

August 10, 2022 by Magenaut

What are the directories one should back up, in order to have a backup of all user-generated files?

Do journaling filesystems guarantee against corruption after a power failure?

August 10, 2022 by Magenaut

I am asking this question on behalf of another user who raised the issue in the Ubuntu chat room.

Bash script to remove the oldest file from from a folder

August 10, 2022 by Magenaut

I want to make a bash script to delete the older file form a folder. Every time when I run the script will be deleted only one file, the older one. Can you help me with this?
Thanks

Showing only “interesting” mount points / filtering non interesting types

August 10, 2022 by Magenaut

I used mount to show mounted drives, I don’t want to see the not so interesting ones (i.e. non-physical). So I used to have a script mnt that did:

How do I find the offset of an ext4 filesystem?

August 10, 2022 by Magenaut

I have a failing hard drive that is unable to write or read the first sectors of the disk. It just gives I/O errors and that is all there is. There are other areas on the disk that seem (mostly) fine.
I am trying to mount a partition (ext4) and see if I can access some files I would like to recover. Since the mount command supports an offset option, I should be able to mount the filesystem even though the partition table is unreadable and unwriteable. The problem is how to find the offset. None of the ext4 tools seems to have this particular feature.