A loop device allows any file to be mounted as a filesystem image. Not to be confused with a loopback interface in networking.

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GNU/Linux: overlay block device / stackable block device

GNU/Linux has union mount that overlays dirs. So you can mount a writeable dir on top of a read-only dir. When the writeable dir is unmounted the read-only dir is untouched. I am looking for the same ...
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When mounting, when should I use a loop device?

According to the following question: What is a "loop device" when mounting? A loop device is a file that acts as a block-based device. While I can understand that conceptually, how is this ...
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How to iterate through a comma-separated list and execute a command for each entry

I have been give a command which outputs a comma-separated list for autosys jobs in the variable $all_jobs: box=box-of-jobs;all_jobs=$(jobscout -box $box | egrep "^\w+" | tr '\n' ',' | sed s/.$//); ...
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Second loopback network interface (for netem)

I would like to add a second loopback network device on Linux, so that I have lo and (e.g.) lo2. This is so that I can use netem to simulate a throttled network over lo2 without compromising my ...
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3answers
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Ensure that loopback root and host are unmounted on shutdown

I'm trying to setup a Linux system that runs from an LVM-formatted image file. After some tinkering with the initramfs and boot options I managed to make it up and running by mounting the host file ...
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Virtual file made out of smaller ones (for mac-like sparse bundle solution)

I'd like to recreate a feature of Mac OS X called sparse bundles (disk images made out of smaller files, making them easy to backup after a small change). For that I'm looking for a way to ...
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How do I setup more then 10 loopback device?

From this answer the solution is to modprobe loop max_loop=64 Which makes me allowed to use 64 loopback devices then mknod -m 660 /dev/loop8 b 7 8 To create the devices. I did this for 8, 9, 10 ...
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Grub change loopback amount?

I'm having an issue with loopback. It looks like there is only 8. I did a search and apparently the problem is grub by default only has 8 loopback (devices?). If i look in /dev/ i see loop 0-7 so that ...
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How to make sure a loopfile is only mounted once?

When mounting a filesystem image via mount -o loop, is there any mechanism to prevent the same file to be mounted a second time?
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loop-device: is this a Linux entity or a lower-level one?

Here's an Ubuntu How-to about booting from ISO-image on flash. http://ubuntuforums.org/showthread.php?t=1288604 What I don't get is creation of loop-device in GRUB2 prior to booting a kernel: ...
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How is the loopback network interface implemented?

The loopback network interface "is a virtual network device implemented entirely in software," according to another question on Unix.SE. But how is this implementation actually accomplished, and how ...
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creating a device image for a network location

I have a dedicated ubuntu server with hetzner.de. hetzner also provides a seperate backup space accessible via samba/ftp/sftp/scp. In their support document about backups, the following line is ...
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How can I mount partitons in a full disk image (i.e. image with partition table) with fuse?

It's a bit indirect, but it's possible mount a partition with a disk image using mount or losetup's "offset" parameter. I'm looking to be able to use fuse to do the same thing in user space Use ...
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2answers
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slitaz 4.0 grub2 loopback concatenate multiple initrd images

I'm trying to get slitaz 4.0 ISO to boot using a grub2 loopback on a multiboot USB; insmod font if loadfont /boot/grub/unicode.pf2 ; then insmod gfxterm # insmod efi_gop # insmod efi_uga ...
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Debian VPS, no loop devices present, modprobe fails

After acquiring a new virtual Debian squeeze I ran into a problem regarding loop devices. My plan was to set up an encrypted FS in a regular file and mount it. Unfortunately I can't do that since ...
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Mounting multiple img files as single loop device

Is there a way to take a disk img file that is broken up into parts and mount it as a single loop device?
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How to remove length limit from losetup -a

I am using losetup -a to see my loop devices, but it has a length limit (which is 62 characters). So I can't know for sure which loop device I really want. Ex: [root@r7byach]# losetup -a ...
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What is a “loop device” when mounting?

I am doing a mounting of an iso file and looking at this tutorial. They use the command: $ mount -o loop disk1.iso /mnt/disk I'm trying to understand the use of -o loop. So I have two questions: ...
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Finding the offset for ext4 partition

I've created an image of my hd with dd, but grub was installed on it, and I'm trying to figure out how to mount the image file, but mount doesn't recognise it as an ext4 partition because of the grub ...