Questions tagged [device-mapper]
The device-mapper tag has no usage guidance.
36
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kpartx does not work as expected inside docker container
I am trying to create disk image inside docker container.
I run the following commands:
Run container with debian
$ sudo docker run --privileged --rm -it debian
Update apt and install packages
# apt ...
0
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0
answers
70
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Additional Keys device with no key holding for repeated input feature - can it be overcome (reWASD?)?
I am choosing additional keys+dial device to use with Photoshop (and in general). My minimal requirements are:
physical dial(s) with each step feedback
"some" amount of buttons
ability to ...
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0
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30
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Why does Windows play a notification sound when I turn on an external light next to my laptop? [duplicate]
This question is similar to (but the answer is not ok):
Why does Windows 8 plays a sound when I switch on an external light?
I have a large fluorescent light above my desktop, sometimes when I turned ...
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0
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26
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Is there a way to preserve persistent device mappings (*not drive letters*) for USB removable drives in Windows? [duplicate]
ATTN moderators: This is a reposting of a question that had been marked as a duplicate, with a reference to this question: Is there any way to force Windows to map inserted USB drives using the first ...
7
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1
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The naming convention of folders in `/sys/bus/usb/devices/`
I am trying to understand the relation between the Linux folder names in /sys/bus/usb/devices/ and the output of lsusb -t.
On my machine, the lsusb shows this:
In the /sys/bus/usb/devices/, there are:...
3
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2
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5k
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"DOS Devices" to directory (aka permanent SUBST) not honored after Windows 21H1 update
Previously, a device mapping had been established using HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\DOS Devices to add an alias from D:\ to C:\Build. This approach discussed in ...
1
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1
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2k
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How to know which is the real drive behind the mapped block device?
I configured my box to boot from an alternative disk through modifying the existing os. However, some partitions are still being mounted from the internal storage.
In the case of the /home partition, ...
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689
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Finding device (manufacturer) details with its device type for the MAC address of a laptop/phone/iPad?
Is there way to find the Device (Or Device manufacturer) details with the MAC address of that device?
I need this, to check whether the connected MACs are Laptop (PC)/Mobile Phones/Tablet (iPads).
1
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0
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305
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Docker DeviceMapper Driver not Freeing Space RHEL 7
I searched around a bit a while back and found stuff about using loop device, which we are not, and using fstrim to free space. I ended up just rebuilding my kubernetes working nodes to clear the ...
1
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306
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lvconvert creating cached LV - results in device-mapper: reload ioctl on (254:0) failed: Invalid argument
On Sles15, after successfully creating the Meta and Cache LVs and combining them with lvconvert, I then go to associate the Cachepool with the slow LV and get the following error:
lvconvert --type ...
1
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140
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LUKS2 - RAID0 - NVME : alignment issue
I have trouble while in top of this stack bellow:
mkfs.ext4 /dev/mapper/raid0luks2
/dev/mapper/raid0luks2 alignement is offset by 147456 bytes
This may result in very poor performance (re-) ...
1
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1
answer
233
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Prevent LVM creating dm-X devices
Was wondering if it's possible to stop LVM on RHEL7 creating symlinks of /dev/dm-X to rootvg?
I'm using my RHEL hosts to connect to SAN LUNs, and prefer to have /dev/dm-X only mapped to multipath ...
0
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1
answer
4k
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Create block device link to target /dev/mapper
Setting up a Full Disk Encryption on Ubuntu derived distro's is easy, because Ubuntu's installer simply provides access to all available partitions on all available disks from within the partitining ...
0
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1
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877
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Disk UUID from blkid output disappears
I'm experiencing a weird situation on RHEL-7. I create a device mapper (crypt) over a disk partition and then copy data (bytes) from disk partition to mapper. The blkid output has two entries for the ...
1
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1
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2k
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udev rules for device mapper when lvm volumes are activated
I currently have a couple of custom udev rules for activating LVM volumes when raid volumes become available that look like this:
KERNEL=="md0", RUN+="/sbin/pvscan --cache -aay"
KERNEL=="md1", RUN+="/...
1
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2
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2k
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A scheme for swap space on a USB
I have recently bought a USB flash drive that I am going to use solely for swap partitions. I understand that swap files on flash media are likely to use up the number of write cycles rather quickly, ...
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1
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240
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Is it possible to test dm's multipath driver without a physical multipath device?
I need to test a scenario that one of our customers has run across using a multipath device. I was hoping to be able to set up a device mapper using the multipath driver pointing to a loop or physical ...
1
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1
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1k
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How do I remove a delay created using dm-delay?
As part of testing my application, I wanted to see what would happen on hard-disk slow down or failure. I added a 500ms delay using dmsetup create delayed. I'm not very familiar with device mapper, ...
1
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0
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759
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How to disable "device mapper" warnings in fedora
Mine is an x86 based embedded platform.. Running completely out of NFS. I recently ported fc23 onto it... But been getting this warning message every time I give the reboot command..
[ OK ] Stopped ...
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1
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560
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Assuming you can't directly boot into a linux system, how do you make the bootstrap?
What are the actual steps, assuming you had a set of c header files that described the memory mapped devices in your system, to make the initial running kernel? I know everyone just boots off a live ...
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1
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2k
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How can I fix my rt (right trigger) bottom on pso2 (Phantasy Star Online 2)
What happened was I was starting up pso2 and everything went okay EXCEPT for one thing. When I tried to get my items in my inventory, it highlighted everything and I can't get the item that I want. ...
0
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1
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2k
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%T specifier in printf option of `stat` command
I want to know what is %T specifier in stat printf option and how it gets the file descriptor value ie., fd,1 is printed by using the below command.
command is
$> echo `stat -L /dev/mapper/...
1
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1
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1k
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How can I export a /dev/mapper mounted filesystem via NFS?
I have a server "pr-cl-n1" that mounts /usr via /dev/mapper like this:
# mount
[...]
/dev/mapper/pr--cl--n1-usr on /usr type ext3 (rw,relatime,errors=continue,barrier=1,data=ordered)
The root of the ...
2
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1
answer
709
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Can I make a encrypted image by using openssl encrypt tools instead of dmsetup?
Generally, I can create a encrypted ext4 image by do this:
fallocate -l 6553600 encrypt.img
losetup -f encrypt.img
dmsetup create encrypt_disk --table "0 12800 crypt aes 32BYTEKEY 0 /dev/loop0 0"
...
1
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1
answer
3k
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dmsetup status fields explained?
I am not new to linux, but I am new to the underlying guts of it, and I don't know anything about LVM or device-mapper. I'm trying to troubleshoot a livecd mounting its live-rw (dm-0) file system as ...
0
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2
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69
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Is there an easy way to retrieve the link speed of network devices?
We have a mix of 100 and 1000mbps cabling in this office with cabling that ranges from ancient home-made cat5 to brand new cat6, and a mish-mash of semi-accessible switches and network segments that ...
0
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0
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2k
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Why do loop devices sometimes refuse to go away?
I regularly mount the partitions inside an image file as loop devices:
sudo kpartx -a test.img
That creates loop devices such as
/dev/mapper/loop0p1
/dev/mapper/loop0p2
When I'm done, I get rid of ...
3
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1
answer
3k
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How to Create Virtual Block Devices
I want to create multiple virtual block devices like /dev/sda and then use them to create an md device for test purpose.
I have mounted my root filesystem on /dev/sda1 and don't have extra space to ...
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3
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2k
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Any way to make partitioning tools see kpartx-created devices?
I have a dd'ed disk image file with me.
I can use a tool like kpartx to create a device-mapper device from this disk image file.
But partitioning programs like gparted and fdisk don't list my ...
1
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1
answer
79
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How to autodetect device name in Linux
I have an encrypted USB dongue with cryptosetup, to mount it I have to execute a script that has hardcoded (or admits it as a parameter) the device name of that dongue that previously you had to ...
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0
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2k
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Udev rule for changing owner of Linux LVM device nodes
I'm having some trouble changing the owner of a Linux LVM logical volume on my Debian wheezy system. I added the following udev rule to both the initramfs and the real root file system:
SUBSYSTEM=="...
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809
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Moxa - NPort 5110 as HTTP Server or similar
I have a NPort 5110 Serial Device Server connecting our Automation Control Box to the LAN so we can communicate with it from a non-local pc via mapped com port. (if you are unfamiliar with the device ...
10
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4
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9k
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TRIM support via dm-crypt/device-mapper
Getting a new laptop with SSD tomorrow. I need to know about the current status of dm-crypt and TRIM. I have seen several conflicting reports and most activity around this question seems to be > 1 ...
2
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0
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318
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How to mount USB disk with LVM/LUKS crypted volumes on a Mac? [duplicate]
Possible Duplicate:
How to mount an encrypted ext3 filesystem under OS X?
I have a USB disk that I've partitioned with LVM and encrypted some of the volumes with LUKS.
This is all Linux/Device ...
1
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6
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95
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Is there some utility that will allow me to see all devices physically connected to my laptop, regardless of whether they have a driver or not?
Upgraded Vista to 7 last day and my wireless laptop adapter is behaving funny.
First it was killing me with resource conflict issues, but I just did a fresh Win 7 installation and the thing just does ...
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0
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860
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How to disable Device mapper package from kickstart?
Can anyone tell me how to disable/exclude Device mapper package from kickstart file.