Cheatsheet of useful Linux commands

sudo mokutil --reset
sudo mokutil --set-sbat-policy delete
sudo reboot

# check state in powershell
Get-Tpm

# open powershell as admin
Disable-TpmAutoProvisioning

# open TPM management as admin
tpm.msc
# and click on "Clear TPM"

# install package
sudo apt install partclone

# run as root:

# for compressed image with gzip
cat dir/sda1.ntfs-ptcl-img.gz.* | gunzip | partclone.restore --restore_raw_file -C -s - -o sda1.img

# for compressed image with zstd
zstdcat dir/sda1.ntfs-ptcl-img.zst.* | partclone.restore --restore_raw_file -C -s - -o sda1.img

# mount extracted image
mount -o loop sda1.img /mnt -t ntfs -o ro

# install package
sudo apt-get install gdisk

# show drive info
sudo gdisk -l /dev/sda

# MBR if output is like:
Partition table scan:
MBR: MBR only
BSD: not present
APM: not present
GPT: not present

# GPT if output is like:
MBR: protective
BSD: not present
APM: not present
GPT: present

# if you are sure you want to have only MBR, you can delete the GPT part
sudo sgdisk -z /dev/sda

# if you are sure you want to have only GPT, delete the MBR part
sudo dd of=/dev/zero of=/dev/sda bs=512 count=1

# check for "not frozen"
sudo hdparm -I /dev/sda

# if drive is "frozen" then issue this command and wait some seconds before powering the computer on again
sudo systemctl suspend

# setting password is needed before issueing command
sudo hdparm --user-master u --security-set-pass password /dev/sdX

# option 1: erase drive (overwrites all user data areas with binary zeroes)
sudo hdparm --user-master u --security-erase password /dev/sdX

# option 2: erase drive (writes predetermined data patterns (set by the manufacturer) to all user data areas, including sectors that are no longer in use due to reallocation)
sudo hdparm --user-master u --security-erase-enhanced password /dev/sdX

# First we want to fill up our pendrive with zeroes
sudo cat /dev/zero > /dev/your_pendrive

# After completion we can check if our flash drive is really wiped with zeros by installing and using a text-based Hex-editor
# Remember: We trust nobody so we check manually if zeros have been written to the drive. If you see weird characters something went wrong.
sudo apt install ht
sudo hte /dev/your_pendrive

# Wipe just a file with zeros:
shred -fvzun 0 file

# Wipe a whole directory recursively with zeros:
srm -rvs directory

# Compare binary files within the console and highlight those areas which differ. Vim and Colordiff have to be installed before.

diff -y <(xxd file.one) <(xxd file.two) | colordiff

lsblk

NAME                        MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINTS
...
sda                           8:0    0    50G  0 disk  
├─sda1                        8:1    0     1G  0 part  /boot/efi
├─sda2                        8:2    0     2G  0 part  /boot
└─sda3                        8:3    0  46.9G  0 part  
  └─dm_crypt-0              252:0    0  46.9G  0 crypt 
    └─ubuntu--vg-ubuntu--lv 252:1    0  46.9G  0 lvm   /

df -Th

Filesystem                        Type      Size  Used Avail Use% Mounted on
...
/dev/mapper/ubuntu--vg-ubuntu--lv ext4       46G  9.5G   35G  22% /
...

sudo gparted

# we want some info about the PV (physical volume):

# 1. sudo pvscan

  PV /dev/mapper/dm_crypt-0   VG ubuntu-vg       lvm2 [<46.93 GiB / 0    free]
  Total: 1 [<46.93 GiB] / in use: 1 [<46.93 GiB] / in no VG: 0 [0   ]

# 2. sudo pvs

  PV                     VG        Fmt  Attr PSize   PFree
  /dev/mapper/dm_crypt-0 ubuntu-vg lvm2 a--  <46.93g    0 

# 3. sudo pvdisplay

  --- Physical volume ---
  PV Name               /dev/mapper/dm_crypt-0
  VG Name               ubuntu-vg
  PV Size               46.93 GiB / not usable 3.00 MiB
  Allocatable           yes (but full)
  PE Size               4.00 MiB
  Total PE              12014
  Free PE               0
  Allocated PE          12014
  PV UUID               zofURa-qyMQ-1hza-DRax-8nvs-mhUR-zZhKgo

# now we want info about the VG (volume group):

# 1. sudo vgscan

Found volume group "ubuntu-vg" using metadata type lvm2

# 2. sudo vgs

  VG        #PV #LV #SN Attr   VSize   VFree
  ubuntu-vg   1   1   0 wz--n- <46.93g    0

# 3. sudo vgdisplay

  --- Volume group ---
  VG Name               ubuntu-vg
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  2
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               1
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               <46.93 GiB
  PE Size               4.00 MiB
  Total PE              12014
  Alloc PE / Size       12014 / <46.93 GiB
  Free  PE / Size       0 / 0   
  VG UUID               55tDXa-6TTg-ccDx-UCCV-UaQX-mnSl-FyP1hi

# now we want info about the LV (logical volumes)

# 1. sudo lvscan

ACTIVE            '/dev/ubuntu-vg/ubuntu-lv' [<46.93 GiB] inherit

# 2. sudo lvs

LV        VG        Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
ubuntu-lv ubuntu-vg -wi-ao---- <46.93g

# 3. sudo lvdisplay

  --- Logical volume ---
  LV Path                /dev/ubuntu-vg/ubuntu-lv
  LV Name                ubuntu-lv
  VG Name                ubuntu-vg
  LV UUID                0RjrOz-HkVm-03XG-GKc7-6YUD-bejn-5kUB54
  LV Write Access        read/write
  LV Creation host, time ubuntu, 2024-11-26 22:11:39 +0100
  LV Status              available
  # open                 1
  LV Size                <46.93 GiB
  Current LE             12014
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           252:1

# step 1: opening the partition
sudo cryptsetup open /dev/sda3 cryptedpartition

# we will find it opened now
ls /dev/mapper

...  cryptedpartition  ubuntu--vg-ubuntu--lv

# lets check it again
sudo fdisk -l /dev/mapper/ubuntu--vg-ubuntu--lv

>>>
Disk /dev/mapper/ubuntu--vg-ubuntu--lv: 46.93 GiB, ...

# step 2: shrinking the ext4 filesystem within ubuntu-lv

# run the mandatory check first
sudo e2fsck -f /dev/mapper/ubuntu--vg-ubuntu--lv

# shrink it, -p stands for showing a progress bar
sudo resize2fs -p /dev/mapper/ubuntu--vg-ubuntu--lv 30g

>>>
The filesystem on /dev/mapper/ubuntu--vg-ubuntu--lv is now 7864320 (4k) blocks long.

# now the filesystem ext4 has a size of 30G (7864320 * 4096 Bytes = 32212254720 Bytes = 30 GiB) 

# step 3: shrinking the LV: ubuntu-lv

# now we reduce the size of the LV to fixed 30GiB
sudo lvreduce -L 30g /dev/mapper/ubuntu--vg-ubuntu--lv

>>>
Size of logical volume ubuntu-vg/ubuntu-lv changed from 46.93 GiB (12014 extents) to 30.00 GiB (7680 extents).
Logical volume ubuntu-vg/ubuntu-lv successfully resized.

# if you look on gparted now, then you ll notice that /dev/sda3 is not filled 100% anymore but shows only 30GiB of usage.

# command not tested but should do the same:
# sudo lvresize --resizefs -L 30g /dev/ubuntu-vg/ubuntu-lv

# step 4: shrinking the VG: ubuntu-vg
# now we need to shink the VG from 46.93 GiB to 30.00 GiB

# if we check the size it should show some free space now
sudo vgs

>>>
VG        #PV #LV #SN Attr   VSize  VFree
ubuntu-vg   1   0   0 wz--n- <49.93g <16.93g

# the only way I found to do steps 4, 5 and 6 at once is to use gparted now to shrink the /dev/sda3 partition manually
sudo gparted

# as mentioned gparted did also take care of this steps:
# step 5: shrinking the PV: /dev/mapper/dm_crypt-0
# step 6: shrinking the LUKS holding partition: /dev/sda3

# other stuff, todo

# now you can mount it like any other partition
# /test ist just my random mountpoint
sudo mkdir /test
sudo mount /dev/mapper/ubuntu--vg-ubuntu--lv /test
# unmounting works also
sudo umount /test
# and do not forget to close the encrypted partition again
sudo cryptsetup close nvme0n1p5_crypt

# sometimes you get an error on closing:
Device nvme0n1p5_crypt is still in use.

# lsof will show you nothing useful:
sudo lsof /dev/mapper/nvme0n1p5_crypt
  lsof: WARNING: cant state() fuse.gvfsd-fuse file system /run/user/1000/gvfs

# but dmsetup does:
sudo dmsetup info -C
                     Open Targ UUID
  nvme0n1p5_crypt       1 1    CRYPT-LUKS2-....
  ubuntu--vg-ubuntu--lv 0 1   LVM-...

# something still holds the nvme0n1p5_crypt active..
# and that is the LVM! so we need to deactivate the VG within the LVM BEFORE we close LUKS!

# find out the name of your VG first:
sudo vgdisplay
  VG Name       ubuntu-vb

# and then deactivate it:
sudo vgchange -a n ubuntu-vg
  0 logical volume(s) in volume group "ubuntu-vg" now active

# now we can close the encrypted partition
# todo

# creating luks partition
sudo cryptsetup luksFormat -c aes-xts-plain64 -s 512 -h sha512 -y /dev/sdX

# mount luks partition
sudo cryptsetup luksOpen /dev/sdX yourDeviceName

# create a filesystem within this luks partition
sudo mkfs.btrfs -L yourLabel /dev/mapper/yourDeviceName #(if you want btrfs)
sudo mkfs.ext4 /dev/mapper/yourDeviceName #(if you want ext4)

# if you want to mount it
sudo mount /dev/mapper/yourDeviceName /yourMountPoint


# generally speaking: mounting your filesystem
sudo cryptsetup luksOpen /dev/sdX yourDeviceName
sudo mount /dev/mapper/yourDeviceName /yourMountPoint

# generally speaking: unmounting your filesystem
sudo umount /dev/yourMountPoint
sudo cryptsetup luksClose yourDeviceName

# Mirroring with rsync from /source to /destination. Compression is great when backing up over the Internet.
rsync --compress --compress-level=9 --human-readable -av --progress --delete --log-file=/path/to/log.file /source /destination

# Rsync command which doesn’t copy everything every time while preserving times:
rsync -avP source destination
#a = archive mode
#v = verbose
#P = show progress

# Backup of harddisks into compressed image file. Due to its multithreading capability pigz is much faster than gzip during compression.

sudo dd if=/dev/sdX status=progress bs=1M | pigz > harddisk.img.gz

# Restore this prior zipped image file and write it directly to disk:
sudo gunzip -c image.gz | sudo dd of=/dev/sdX status=progress bs=1M

# Recover a Linux Soft-RAID md/5:

sudo mdadm --assemble --scan
sudo cryptsetup luksOpen /dev/md/5 temp
sudo mount /dev/mapper/temp /your_path

# Mount a Linux Soft-RAID manually:

sudo mdadm --examine /dev/sdX
sudo mdadm -A -R /dev/md9 /dev/sdX
sudo mount /dev/md9 /openedRaidPartition

# And close it again:
sudo umount /openedRaidPartition
sudo mdadm -S /dev/md9

# List all loadable kernel modules:

find /lib/modules/$(uname -r) -type f -name \*.ko

# Template for configuring a fresh manjaro xfce installation:

#update system
sudo pacman -Syyu
 
#install zshell
sh -c "$(curl -fsSL https://raw.github.com/robbyrussell/oh-my-zsh/master/tools/install.sh)"
sudo pacman -S powerline-fonts
 
#install virtualbox
sudo pacman -S virtualbox
 
#copy fonts which you need into /usr/share/fonts and run
sudo fc-cache
 
#fixing the Manjaro Linux XFCE text shadow problem on the desktop
xfconf-query -c xfce4-desktop -p /desktop-icons/center-text -n -t bool -s false

# Nice to have Manjaro packages:

gufw (firewall gui)
chromium (browser)
synapse (launcher)
psensor (temperature)
ether (pendrive tool)
file-roller
p7zip zip unzip unrar
tilda (background terminal)

# Laravel development quickstart:

git clone project.git
cd project
composer install
composer update
cp .env.example .env
php artisan key:generate
php artisan serve --port=8000

# Add to /etc/ssh/sshd_config:

Subsystem sftp internal-sftp
 
  Match Group sftpusers
  ChrootDirectory %h
  ForceCommand internal-sftp
  AllowTcpForwarding no
  X11Forwarding no

# Adding user and change configuration:

useradd newuser
usermod -s /bin/false newuser
chown root:root /home/newuser
chmod 755 /home/newuser
mkdir /home/newuser/writablefolder
chown newuser:newuser /home/newuser/writeablefolder
chmod 755 /home/newuser/writeablefolder
 
groupadd sftpusers
usermod -G sftpusers newuser
 
service sshd restart
service vsftpd restart

# Replacing a broken harddisk (/dev/sda) with two partitions with RAID1 (md0 + md1):

# after having replaced the harddisk; copying MBR partition table
sfdisk -d /dev/sdb | sfdisk /dev/sda

# adding partitions to existing RAID-array md0 and md1:
sudo mdadm /dev/md0 -a /dev/sda1
sudo mdadm /dev/md1 -a /dev/sda2

# reinstalling grub on both disks again, leave options empty, select two disks (/dev/sda + /dev/sdb)
sudo dpkg-reconfigure grub-pc

# Bash: iterate through all files within a specific folder and count its files

for i in /folderpath /folderpath ; do 
    echo -n $i": " ; 
    (find "$i" -type f | wc -l) ; 
done

# converting image
qemu-img convert -f qcow2 -O raw image.qcow2 image.img

# creating VM in proxmox
qm create 120 --bootdisk scsi0

# importing disk to someStorage (as named in "pvesm status")
# importdisk adds the image as unused disk
qm importdisk 120 someImage.img someStorage

# attaching the image to the VM. still needs to be marked as boot device by hand
qm set 120 --scsi0 someStorage:vm-120-disk-0

# "zpool status" output during normal operation

  pool: rpool
 state: ONLINE
  scan: none requested
config:

	NAME                                             STATE     READ WRITE CKSUM
	rpool                                            ONLINE       0     0     0
	  mirror-0                                       ONLINE       0     0     0
	    ata-SanDisk_SDSSDH3_2T00_193732800276-part3  ONLINE       0     0     0
	    ata-SanDisk_SDSSDH32000G_192970802134-part3  ONLINE       0     0     0

errors: No known data errors

# "zpool status" of degraded state if we unplug /dev/sdb manually

  pool: rpool
 state: DEGRADED
status: One or more devices could not be used because the label is missing or
	invalid.  Sufficient replicas exist for the pool to continue
	functioning in a degraded state.
action: Replace the device using 'zpool replace'.
   see: http://zfsonlinux.org/msg/ZFS-8000-4J
  scan: none requested
config:

	NAME                                             STATE     READ WRITE CKSUM
	rpool                                            DEGRADED     0     0     0
	  mirror-0                                       DEGRADED     0     0     0
	    ata-SanDisk_SDSSDH3_2T00_193732800276-part3  ONLINE       0     0     0
	    ata-SanDisk_SDSSDH32000G_192970802134-part3  UNAVAIL      3   212     0

errors: No known data errors

pool: rpool
 state: DEGRADED
status: One or more devices could not be used because the label is missing or
	invalid.  Sufficient replicas exist for the pool to continue
	functioning in a degraded state.
action: Replace the device using 'zpool replace'.
   see: http://zfsonlinux.org/msg/ZFS-8000-4J
  scan: none requested
config:

	NAME                                             STATE     READ WRITE CKSUM
	rpool                                            DEGRADED     0     0     0
	  mirror-0                                       DEGRADED     0     0     0
	    ata-SanDisk_SDSSDH3_2T00_193732800276-part3  ONLINE       0     0     0
	    14464946144281260868                         UNAVAIL      0     0     0  was /dev/disk/by-id/ata-SanDisk_SDSSDH32000G_192970802134-part3

# copy partition table from good /dev/sda to new /dev/sdb
sgdisk -R /dev/sdb /dev/sda
sgdisk -G /dev/sdb

# copy the bios and efi boot partitions
dd if=/dev/sda1 of=/dev/sdb1 bs=512
dd if=/dev/sda2 of=/dev/sdb2 bs=512

# replace command
zpool replace rpool ata-SanDisk_SDSSDH32000G_192970802134-part3 /dev/sdb3

# show raid status
zpool status

# show all your disk IDs
ls -l /dev/disk/by-id/

perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
  LANGUAGE = (unset),
  LC_ALL = (unset),
  LC_CTYPE = "UTF-8",
  LANG = "en_US.UTF-8"
    are supported and installed on your system.
perl: warning: Falling back to a fallback locale ("en_US.UTF-8").

# fixing it

sudo locale-gen en_US.UTF-8
sudo localedef -i en_US -f UTF-8 en_US.UTF-8

sudo nano /etc/environment

+export LANGUAGE=en_US.UTF-8
+export LANG=en_US.UTF-8
+export LC_ALL=en_US.UTF-8

# You can get some detailed information about the fitness of /dev/md0 by issuing:

cat /proc/mdstat

# An exemplary entry looks like this:

Personalities : [raid1]
md0 : active raid1 sdb1[1] sda1[0]
      136448 blocks [2/2] [UU]

sudo mdadm --manage /dev/md0 --fail /dev/sdb1

sudo mdadm --manage /dev/md0 --remove

# copy sda to sdb (GPT)
sudo sgdisk -R /dev/sdb /dev/sda

# create UUID
sudo sgdisk -G /dev/sdb

# copy sda to sdb (MBR)
sudo sfdisk -d /dev/sda | sudo sfdisk /dev/sdb

sudo mdadm --manage /dev/md0 --add /dev/sdb1

Personalities : [raid1]
md0   : active raid1 sdb1[1] sda1[0]
      1464725760 blocks level 5, 64k chunk, algorithm 2 [6/5] [U_]
      [==>..................]  recovery = 12.6% (37043392/292945152) finish=127.5min speed=33440K/sec

# installing GRUB
sudo grub-install /dev/sda

# update the system
sudo apt update && sudo apt upgrade && sudo apt autoremove

# useful stuff
sudo apt install curl htop neofetch ncdu wget unrar git p7zip-full vlc

# install vbox according to https://freundschafter.com/how-to-install-virtualbox-7-1-on-ubuntu-24-04/

# install media codecs
sudo apt install ubuntu-restricted-extras

# enable minimize on click (on a symbol in dock)
gsettings set org.gnome.shell.extensions.dash-to-dock click-action 'minimize'

# further stuff if needed
# https://kskroyal.com/ubuntu-24-04-post-install-steps