LUKS (Linux Unified Key Setup) is a disk-encryption specification.

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How to open a port early in boot process to unlock LUKS via SSH

I have a fully encrypted server running Debian 7 and have set up dropbear and busybox to unlock the LUKS container via SSH (as described in this tutorial and in this U&L answer). Unfortunately, ...
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How to mount a cryptsetup container just with `mount`?

I created an encrypted container via #!/bin/bash dd if=/dev/zero of=$1 bs=1 count=0 seek=$2 MAPPER=$(mktemp -up /dev/mapper) LOOPDEV=$(losetup --find --show $1) cryptsetup luksFormat $LOOPDEV ...
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Which partitions should I encrypt?

My laptop is currently running Windows and Fedora, but I'm planning to install Arch Linux as my sole OS soon. This current setup is using whole disk encryption through TrueCrypt, but I'm unsure if it ...
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How to choose LUKS encryption when installing RHEL 6?

With the default RHEL 6 installer, how can I choose the LUKS encryption? Afaik if I prepare the disk like cryptsetup luksFormat -c cast5-cbc-plain -s 128 /dev/$DEVICE could be the "fastest" ...
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How to have Linux wipe/randomize/sanitize RAM at shutdown?

For mysterious reasons I still double boot sometimes into Windows. My problem is that I fear that information may leak because the RAM memory is accessible to Windows. (the Linux partitions are ...
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Trying to understand LUKS encryption

I decided to encrypt my root partition with LUKS+LVM. My ThinkPad setup: Samsung 830 128GB SSD 750GB HDD Core 2 Duo 2,5 GHz P9500 8GB RAM But the more I read, the less I understand about those ...
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Why are logical volumes used with LUKS partitions?

All of the instructions I've seen on setting up a LUKS encrypted drive require using logical volumes to create root and swap partitions inside a LUKS device. Why not just put standard partitions ...
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Umount all attached usb disks with a single command

Is there a (safe) way to umount all partitions on all attached usb devices (usb-hdds, usb-sticks) with a single commandline command, including several encrypted luks partitions? Only the partitions ...
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Linux: LUKS and multiple hard drives

I have a Debian Linux system (amd64) installed on a RAID-1 system encrypted device (LVM on LUKS) and will have a RAID-6 of >=4 disks where I'll put my data (LUKS and maybe LVM). I think the basic ...
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RHEL6 LUKS with TPM support?

I'm surprised that this question is not asked more frequently, but (in RHEL) does LUKS support TPM's the way that Windows BitLocker does? If so, how is this feature implemented, and does it provide ...
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Can I overwrite LUKS partition with it's decrypted content?

I have HDD with my data (partial backup of most important data available on other HDD), currently it's formatted as Ext4 over LVM over LUKS. I want to remove LUKS layer, but reformatting and data ...
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Are there more advanced LUKS key schemes, e.g. 2 of 3 keys needed?

It seems like the two main LUKS encryption options are: USB keyfile (see http://superuser.com/questions/149578/how-can-i-use-a-keyfile-on-a-removable-usb-drive-for-my-encrypted-root-in-debian) ...
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247 views

LUKS encryption for tape media?

I was wondering, if it was possible to use LUKS encryption with tape drives, QIC for instance. I'm using LUKS for USB drives and internal disks, even DVDs and CDROMs. But I was thinking of maybe ...
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Poor IO due to LUKS/Software RAID/LVM ordering?

I'm trying to determine if I should re-setup my RAID array due to poor IO performance. First off, the system: i7 920 4 4TB WD 5400 Green drives CentOS 6.3 host Secondly, the disk setup: ...
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How to decrypt an encrypted container via ssh without entering a passphrase while requiring some client authentication?

I log in to a server via public key authentication and then mount a container (using e.g. LUKS/dm-crypt or truecrypt). At the moment, I have to enter the container password manually. Is there a way to ...
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How can I get a HASH of the LUKS master key?

From: https://code.google.com/p/cryptsetup/wiki/FrequentlyAskedQuestions 6.15 Can I clone a LUKS container? You can, but it breaks security, because the cloned container has the same ...
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Best practice to backup a LUKS encrypted device

What's the fastest method to backup and restore a luks encrypted device (e.g. a full encrypted usb-device to a image-file). The usb-device can be decrypted/accessed. I'm looking for a solution to ...
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1answer
188 views

How can the root file system be accessed to launch cryptsetup to allow access to the root file system?

I have got laptop with full disk encryption. There is a /boot partion which is not encrypted and the other partition /dev/sda5 is. In order to decrypt, it asks me for the passphrase which is then ...
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How to remove LUKS encryption?

I tried removing LUKS encryption on my home directory using the following command: cryptsetup luksRemoveKey /dev/mapper/luks-3fd5-235-26-2625-2456f-4353fgdgd But it gives me an error saying: ...
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Why does LUKS need to generate hash values?

If you create a new LUKS device, you can specify the option -hash and -iter-time. For example like this: sudo cryptsetup luksFormat --cipher aes-cbc-essiv:sha256 --key-size 256 --iter-time 2100 ...
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cryptdisks_start: precheck failed: the device contains a filesystem type crypto_LUKS

I'm trying to use cryptdisks_start to open a LUKS device that is defined in my /etc/crypttab. Unfortunately, the command fails with the following error message: martin ~ # cryptdisks_start ...
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LUKS storing keyfile in encrypted usb drive

I already asked once about LUKS unlocking of multiple HDDs in Linux: LUKS and multiple hard drives. Now I would like to know how to secure store the keyfile used for the automatic unlock of the ...
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How can I shrink a LUKS partition, what does `cryptsetup resize` do?

I am in progress of resizing a LUKS encrypted partition that contains a single ext4 filesystem (no LVM or something). The cryptsetup FAQ recommends to remove the old partition and recreate it, but ...
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Can I use scrypt to hash for LUKS?

Can scrypt be used as the hashing algorithm for LUKS? Can I tune its parameters? How can I do this?
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How to set laptop screen brightness just after boot with full disk encryption

my girlfriend bought Lenovo Essential G500 i5-3230 and I installed Linux Mint 16 on it with full disk encryption. It is standard installation with encryption using dmcrypt and LUKS. But there is a ...
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Are remote LUKS volumes mounted locally with sshfs made visible to remote users?

I created an encrypted volume with LUKS and uploaded it to a remote directory on an untrusted host. I can mount it locally though. I first mount the remote directory locally with sshfs and then open ...
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How to salvage a lvm/luks install from custom install

I was battling with setting up a Mint install on an encrypted hard-drive, and I think I partially succeeded. But I cannot boot the system because some configuration is not correct, and since I'm a ...
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How to decrypt LUKS with the known master key?

From: https://code.google.com/p/cryptsetup/wiki/FrequentlyAskedQuestions CLONING/IMAGING: If you clone or image a LUKS container, you make a copy of the LUKS header and the master key will stay the ...
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parted: create new partition

I have a 3TB disk, and I understand I have to use parted if I want to create a partition bigger than 2TB. All right then. parted /dev/sdb (parted) mklabel gpt (parted) mkpart primary ...
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1answer
207 views

Open luks-encrypted partition from virtual DomU LVM disk containing another LVM

I've gotten myself in a bit of a bind, here. A while ago I set up an encrypted Unbuntu 13.04 under Xen. It's virtual disk is an LVM LV. This LV was presented to the DomU as a (whole) physical disk ...
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How to open multiple LUKS volumes with key entered in initramfs?

I have a Debian 7.4 (stable) based server configured to use an encrypted (RAID1 + LVM) root partition (/boot is un-encrypted regular partition) to which I installed dropbear SSH server so I can ...
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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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forgot to luksClose usb persistent partition, is this a problem?

Following the Kali Linux documentation for "Adding USB Persistence with LUKS Encryption", I created a persistent partition and encrypted the volume with: cryptsetup --verbose --verify-passphrase ...
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How to use a samba login to mount a luks container?

Our server has an (dm-crypt/LUKS) encrypted project directory which is currently mounted via SSH before its samba share can be accessed - and obviously no one remembers to unmount it afterwards. ...
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BCache and disk encryption

I recently bought a new laptop with a 16Gb mSATA SSD cache drive. I haven't used that one yet. I have, however, opted for Ubuntu 13.04 with "Full Disk Encryption" for the main partition (is that ...
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after adding one more physical volume and enlarging logical volume, grub fails

Several years ago I installed Debian on my 500 GiB hard disk. During installation I chose to have encrypted filesystem. So installer created one small unencrypted boot partition (I guess that grub ...
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Any reason not to use LUKS on a backup drive?

I have my hard disk encrypted with LUKS, but I make regular backups to an unencrypted external harddrive. Is there any reason I shouldn't setup LUKS on my backup drive as well? Obviously, the big ...
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Detecting the device of a crypto mount

I have an external eSATA-hdd on an OpenSUSE 12.2 system. The external hdd has an LVM on a dm-crypt partition. I mount it by powering it up and then doing rescan-scsi-bus.sh cryptsetup -v luksOpen ...
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Decrypt second encrypted LVM during headless server boot?

I've followed this question https://unix.stackexchange.com/questions/5017/ssh-to-decrypt-encrypted-lvm-during-headless-server-boot and successfully remotely decrypted my root drive. However, I have a ...
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1answer
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Filesystem types for encrypted partitions

I wish to encrypt two external hard drives using dm-crypt/LUKS for whole-disk encryption. I want one hard drive to have an ext4 filesystem for Linux use only, and the other to have an NTFS filesystem, ...
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How can move a LUKS container from the middle of a partition to the beginning?

For the tl;dr, skip to the bottom. I have a dual-boot setup with Mac OS X at the beginning of my drive and three GNU/Linux partitions at the end of the drive. I don't have the relevant machine on ...
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1answer
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Boot resolution change in initramfs on laptop monitor and HDMI monitor

I have Linux Mint 17 on my laptop. Also I have 22'' monitor connected to laptop using HDMI cable. My disk if fully encrypted with LUKS and LVM. On boot I get graphical prompt to enter password for ...
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1answer
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Auto de-crypt all LUKS partitions in Debian

I use Debian Wheezy and have all partitions encrypted using LUKS, except /boot. I want to decrypt the partitions automatically without having to type the password in each of the 7 encrypted partitions ...
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Automatically suspend luks volume after delay

Anyone have any ideas for how I can automatically do a luksSuspend on a luks volume after it's been unused for a certain amount of time. I was thinking of just scheduling a command with crontab or ...
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LUKS: encrypted device is much smaller than its host partition

To store personal data, I have encrypted a partition with LUKS but, according to the file manager, the resulting encrypted device is much smaller: 334 GB versus 385 GB. However, the Disk Utility in ...
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expanding boot, moving LUKS root

GPT > Partition2 > LUKS > btrfs I need some additional space for my boot volume, so far I did: Shrink my btrfs volume by 250MB. btrfs resize -250M / Shrink the LUKS root volume cryptsetup ...
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luks single signon

I've got LUKS (Linux Unified Key Setup) running on a couple of my Linux boxes. I've looked online but haven't seen anyone document how to make it work in a single signon option, but was hoping ...
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Install Backtrack 5 r2 into running LUKS setup installed with ubuntu

One Harddisk (sda) Two Partions. With a working ubuntu running. 1) /boot 2) LVM with this virtual volumes/partions/ or whatever they are called inside: Swap Ubuntu Home Prepared for Backtrack Of ...
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Overwriting disk before encryption

I'm going to create encrypted lvm on my disk. As a encryption mechanism I choose dmcrypt with LUKS. Here's my question - should I overwrite (for security reasons) whole disk before creating encrypted ...
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Cannot mount filesystem under luks. Device does not exist

I made one big luks device and re-used it on my debian install, then i ran into some boot problems and i need to acess the filesystem. The problem is, i decrypt the luks device and when i try to ...