Questions tagged [block-device]
The block-device tag has no usage guidance.
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How can I access a block device file as a regular file with defined size in Linux?
I need to transfer all the data from an external hard drive through the internet, including its partition table, boot sector - everything -, but I don't have space anywhere to copy that entire hard ...
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How can there be different tracks from optical media exposed to the PC? [duplicate]
Ok so bear with me.
An Audio CD has different 'tracks', right? Not the songs, but like an audio track, a data track etc. Only the data track contains a proper filesystem (and normal block sizes) as we ...
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Why does lsblk report partition as "null" from within a docker container?
The following lsblk command returns "null" for several fields when called from within my archlinux container. On my natively running system the lsblk command returns values for all fields as ...
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Why are there two mechanisms to remove/hide disks in Linux?
I'm using Linux from external drive. I don't want it to see primary disk with Windows at all. In the past I have been doing that by writing 1 to /sys/block/devices/sd*/device/delete (writing from ...
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btt in blktrace tool does not report any data in android
I have collected trace data in file parse.bin with blktrace in android.
Then I use btt to parse the cellocted data as below:
/ssd/blktrace/btt/btt -i parse.bin
But it does not report any data. The ...
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390
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Can I mount an empty qcow2 image?
I am trying to mount my image.qcow2 to nbd device on my linux machine using the following command:
guestmount -a test.qcow2 -i --ro /mnt/test_qcow/
but I get the following error:
guestmount: no ...
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rhel + disk util is very high , what is the impact for long term
we have backup server with rhel version 7.2
server is VM machine , and OS disk is VMDK disk
disk used space is around - 50% , and from smartctl we not see problem
as we can see from follwing details
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How to read tmpfs as a block device in linux?
A typical linux machine mounts a tmpfs to store temporary files:
$ df
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 953M 702M 203M 78% /
tmpfs 1.5G ...
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How to let xz show percentage progress when compressing block device in Linux?
When I use xz to compress a block device (e.g. /dev/sda1), --verbose shows the current size read from input file (128 MiB below). However, it does not show the percentage of input file read (--- % on ...
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Same file system but different hardware abstraction confusion
I still don't fully grasp how file systems work deep down.
For example, I have both a hard disk drive and a Flash USB stick connected to my Linux or Windows computer.
I'm presented with options of ...
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how to dd /dev/sdX to /dev/mmcblkX?
I made a Debian 10 system image in virtual machine and written it to external HDD. I wanted to copy the system to a laptop's disk, but it has SSD disk that shows up as /dev/mmcblk.
My system has 3 ...
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How to make a swappable in-memory block device in Linux without tmpfs?
One can make a ramdisk in Linux by modprobe brd rd_nr=1 rd_size=$SizeInKB (creates uncompressed /dev/ram0) or by modprobe zram && echo $SizeInBytes >| /sys/block/zram0/disksize (creates ...
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In reference to disks "allocation unit", "block", and "cluster" synonyms?
In the context of spinning disk media such as floppy and hard disks, do these terms all refer to the same underlying concept, differing only by which term is used by which platform?
allocation unit
...
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What's the minimum number of lba I can trim (sg_unmap) from a device?
I run this command:
sg_unmap -v -l 0 -n 1 DEVICE
and it doesn't fail but it also doesn't do anything.
when I increase it to n=8 then it's trimming 8 lbas
why it's working like that? I couldn't ...
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Why BlockDeviceMapping does not create UUID?
In Linux machines, block devices have UUID
Below is the CloudFormation template:
"BlockDeviceMappings": [
{
"DeviceName" : "/dev/sdf",
"Ebs" : {
...
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