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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I am facing hoping issue in my script, please help me [on hold]

for i in `ls -ltr | grep ' Nov' | awk '{print $NF}'` do for j in `unzip -l $i | grep -i SystemOut | awk '{print $NF}'` do unzip -c $i | grep -i Live | grep 'smarter planet' done ...
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41 views

cryptsetup: Attaching loopback device failed

I am using cryptsetup with detached header. For that I am using the --header parameter, to specify header file. I can open my device using: cryptsetup luksOpen /dev/sdb1 sdb1 --header LUKS-HEADER ...
2
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1answer
891 views

Problem creating raw disk image and mounting it in rescue mode to QEMU

I am trying to create booting system from raw disk image. This is what I do: $ dd if=/dev/zero of=system2.img bs=1M count=6000 6000+0 records in 6000+0 records out 6291456000 bytes (6.3 GB) copied, ...
0
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1answer
38 views

Compare a certain lines from multiple documents

I want to compare a certain lines in a multiple documents. I tried using diff and comm, but the conditions are these, the documents are in a different working directory/folder, I could use a ...
1
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1answer
28 views

Using Device mapper thin provisioning on loop devices

I have several KVM raw files that are read only (about 100gb). I am adding these raw files as loopback devices. I then create a snap file to allow the VM to have read/write access to its disk. This ...
3
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4answers
348 views

How do you create a for loop with a changeable number of iterations?

How do you iterate through a loop n amount of times when n is specified by the user at the beginning? I have written a shell script and need to repeat a certain part of it n numbers of times ...
4
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1answer
275 views

File containing ext filesystem

Let's suppose I create a file, map it to /dev/loop0, and create a LUKS partition inside dd if=/dev/zero of=myfile bs=1M count=1000 losetup /dev/loop0 myfile cryptsetup -c aes-cbc-essiv:sha256 -s 256 ...
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42 views

Creating a sparse (automatically expanding and contracting) swap file with hole-punching support

I have this crazy idea, and want to know the pitfalls of such an approach (or whether it can even work with no deadlocks.. etc). The goal is to create an automatically expanding and contracting ...
5
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3answers
6k views

How to add more /dev/loop* devices on Fedora 19

How to add more /dev/loop* devices on Fedora 19? I do: # uname -r 3.11.2-201.fc19.x86_64 # lsmod |grep loop # ls /dev/loop* /dev/loop0 /dev/loop1 /dev/loop2 /dev/loop3 /dev/loop4 /dev/loop5 ...
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1answer
90 views

Breaking out of while loop with a switch case inside

I am having an issue with exiting a bash script out of a while loop: while read -r dir event name; do case $event in OPEN) chown $VHOST:$VHOST $WEBPATH/$name; echo "The file \"$name\" ...
0
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1answer
39 views

Decrypting a previously create losetup device

I've created an encrypted backup in 2004, using losetup -e. I still know the passphrase, so I should be fine, but losetup is gone in the linux distributions I use. I still have a bash script for ...
0
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41 views

Make whiptail work in a for loop

This is my first question ever here... So please be gentle :) I have a bash script that checks ping for 163 sites(stores around the country), which is this: #!/bin/bash #storestest.sh #version 0.9.2 ...
1
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0answers
7 views

Is it safe to modify underlying file if it's mounted by losetup?

I've got a raw binary file and I need to access it (read-only) as a block device, for compatibility reasons. I mount this file through losetup eg. losetup /dev/loop0 file.bin. The block device is only ...
8
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4answers
3k views

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?
2
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5answers
81 views

Looping through a file using a column

I am trying to loop through a file named file.txt that contains a bunch of junk and one column (column #4) I am interested in. I want this loop to run from 0 to eof. For each value in column 4, I want ...
0
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1answer
14 views

Creating a function that reads off an input list of files

I am new to UNIX/Linux and am in the process of writing bioinformatics pipelines. These pipelines take in input files and pass them through multiple packages. Say there is a list of files that goes ...
0
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1answer
45 views

Bash For Loop - prompt for IP range and password

I have a simple for loop one liner I use to check for things across a number of servers that have the same password set. I want to develop this one liner into a script that logs into a cluster of ...
2
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1answer
26 views

combining output from different scripts into different files in a loop

First of all: I hope the question is comprehensible, otherwise please let me know and I will do my best to make it more clear. This is a follow up to Replace one entire column in one file with a ...
2
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2answers
30 views

bash: how to add assigned value to file

I have bash script looping through several files in a directory. The file identifier has been saved as a variable $num. What I would like to do is add $num as another column in my data like in the ...
3
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1answer
41 views

Get target device by /dev/dm-X entry

I have to map several loopback devices via dmsetup. I could track which loopback device is mapped to a particular /dev/dm-X device file, but is there an easy way to get this info by the /dev/dm-X ...
2
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0answers
114 views

Unable to mount secondary HDD on CentOS 6.7 (Must specify file system?)

I have a secondary HDD that worked fine in Ubuntu 13.04. I had mounted in to /media/user/<some UUID>/. I could read and write files without problem. My Ubuntu installation was on a primary SSD. ...
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3k views

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 ...
12
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3answers
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Creating formatted partition from nothing

I need to create filesystem with just one partition from nothing (/dev/zero). I tried this sequence of commands: dd if=/dev/zero of=mountedImage.img bs=512 count=131072 fdisk mountedImage.img n ...
0
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1answer
46 views

How to copy/burn a loop device image to a partition?

I'm building a rootfs for a embedded device. I start by making an empty loopback file system, then mount it, and add files to it. When I finish, I end up with a file system image. Then I can burn ...
0
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1answer
114 views

What is the difference between loop device and block device? [closed]

I want to create a loop device myself, I want it to have a special name, say /dev/loop-test-0. I want it to be up after I reboot the machine. I though that I can use mknod for this, but this doesn't ...
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2answers
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busybox initramfs loop mount

I'm trying to loop mount my root filesystem (a loop file) within a busybox initramfs. I try to run the command: mount /rootfs.raw /root ... which works on my Ubuntu laptop, however, I simply get ...
4
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3answers
443 views

Bash script: do something one time inside a loop then stop, but continue looping

I have a Bash script that checks my laptop battery and sends me an Android notification (via shuttle, a Bash script I wrote that serves as a cli interface for the Pushbullet API). It works nicely, but ...
0
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2answers
213 views

breaking out of command loop but exit code not the reason?

I run the following: echo "while emacs;do echo $?;done;echo Exit code: $?;" | bash If I exit emacs through the menu or the close button, it prints exit code 0 and restarts. If I exit emacs through ...
2
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2answers
2k views

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 ...
2
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1answer
833 views

unetbootin: cannot mount squashfs on loop device

Im having a bit of fun with unetbootin with linux mint 16 setup in it. However when I try run the default menu item I get an error that ends with this: can not mount /dev/loop0 ...
0
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1answer
43 views

How can I loggin from VM1 to VM2 using script?

I am using script to loggin my VM2 from VM1 (Password of the VM2: fifa): for i in {a..z}{a..z}{a..z}{a..z} do # $i as a password ssh root@ipaddress read i echo $i done bit it doesn't work. ...
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1answer
55 views

How to troubleshoot disk controller on Illumos based systems?

I am using OmniOS which is based off of Illumos. I have a ZFS pool of two SSD's that are mirrored; the pool, known as data is reporting its %b as 100; below is iostat -xn: r/s w/s kr/s kw/s ...
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572 views

How to atomically allocate a loop device?

I am writing some shell scripts to handle some disk image stuff, and I need to use loop devices to access some disk images. However, I am not sure how to properly allocate a loop device without ...
0
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2answers
78 views

Variable in for loop to be used as an array for a csv output

I've been struggling to come up with a solution for this, the goal is to organize the results into comma separated columns as we have to recable our entire datacenter from cat6 to cat6a. $DBFILE ...
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101 views

Running FFmpeg in While Loop

Here is my problem. I want to run many different multiple ffmpeg instances all in background and all in while true loop. I tried the following command but does not even work: (while true; do ...
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2answers
253 views

How do users mount .bin/.cue or .iso with loopback device as read only?

Can users mount any of the following image files as read-only using a loopback device? If it is possible then can anyone give me examples?
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1answer
346 views

Installing Arch Linux on an SSD

I'm making my way through this: https://wiki.archlinux.org/index.php/Beginners%27_guide I've done this successfully a couple of times when working with conventional HDDs but I've recently bought and ...
5
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How can I partition a volume in a regular file without loop?

I'm trying to play around with OS development, and I started with a boot loader, where phase 0 loads phase 1 from a file (specified by inode) on an ext4 partition (specified by first LBA). Of course, ...
1
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1answer
107 views

BASH: looping through ls [duplicate]

I'm having trouble with this piece of code: 22 for filename in "$( ls "$1" | grep ".*\.flac$" )"; do 23 file_path="$1${filename}" 24 ffmpeg -i "${file_path}" -f ...
0
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110 views

SED: print entire paragraph for specific pattern while loop

I find partial answer about my problem on this question but i still have trouble. I need to use a variable as a pattern for the sed command in a loop sed -e '/./{H;$!d;}' -e 'x;/'$var'/!d;' The ...
3
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2answers
628 views

Generating a .img from tarball: The /dev/loop devices

I'm trying to make a .img from a tarball using the following script I found: #!/bin/bash # Packages required # dosfstools parted # Can be run on any Linux system # loop.max_part=15 must be in ...
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66 views

FTDI FT2232H time setting

I used FTDI FT2232H in MPSSE mode, running it at 30MHz(maximum speed) clock rate and Latency Timer is 255, I have downloaded libraries from below link and compiled with my App. code: ...
3
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3answers
210 views

Create Linux distro with minimal number of files

I'm thinking about designing a system for a project using some single-board computer (RaspberryPi, CubieTruck etc) that runs Linux. My main requirement is keeping the complexity of the booted SD card ...
3
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2answers
4k views

Mount an ISO virtually using /dev/sr0 device

I'm doing a study about how CD-ROM can be mounted virtually and all I could find out was mounting using loop devices. mount -o loop disk1.iso /mount-point This is fairly easy. I understand that ...
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4answers
776 views

Executing a command within `if` statement and on success perform further steps

I was trying to execute a program which will create a directory on the basis of a complete path provided to it from the prompt and, if the directory already exists it will return an error (for ...
3
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1answer
200 views

How to find which images belong to which /dev/loop?

I work a lot with imaged drives, meaning a do a dd-copy of the drive in question and then work on the image instead of the drive itself. For most work, I use kpartx to map the drive's partitions to a ...
13
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3answers
3k views

How to setup a growable loopback device?

I know I can create and use a loopback device like this: # Create the file truncate disk.img --size 2G # Create a filesystem mkfs.ext4 disk.img # Mount to use mount disk.img /mnt # Clean up umount ...
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212 views

Loopback (bind) mount automatically mounting additional ext4 USB drive

I have a USB (ext4) drive connected and it's registered in /etc/fstab. It mounts at /media/Backup fine. I want to mount a specific directory on that drive using a bind / loopback mount (this is ...
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248 views

UDEV rule to run partprobe on loop device

I use udisks2 to mount raw image over a loop device: udisksctl -f image.img --no-user-interaction Policykit is configured, so no errors here. For some reason kernel does not want to re-read ...
2
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2answers
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mount: could not find any free loop device

When I try to mount an ISO image with mount -o loop I get mount: could not find any free loop device Running losetup -a shows /dev/loop0: [0005]:2464 (/dev/sda1) /dev/loop1: [0005]:3439 ...