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Create a script file night_mode

#!/bin/sh

night_mode() {
    xrandr --output VGA-1 --gamma $1 --brightness $2
}
case $1 in
  off) night_mode 1:1:1 1.0 ;;
  *) night_mode 1:0.85:0.6 1.0 ;;
esac

Assume we have 2 partitions: /dev/fedora/root and /dev/fedora/home, want to reduce the size of root and give it for home.

Boot to live boot USB.

Ensure that partitions are not mounted.

For read from pipe: $ alias less="vim -u /usr/share/vim/vim*/macros/less.vim -" For read from file: $ alias fless="vim -u /usr/share/vim/vim*/macros/less.vim"

If ssh key (~/.ssh/id_rsa*) is not available, create new $ ssh-keygen Copy the public key to remote host $ ssh-copy-id -i ~/.ssh/id_rsa.pub <user>@<remote-host>

Use sed and md5sum $ sed -n <begin_line>,<end_line>p <file_name> | md5sum For example, to get checksum from line 2 to line 15 in a file sample.txt $ sed -n 2,15p sample.txt | md5sum

Update file /etc/apt/sources.list deb http://archive.debian.org/debian <code_name> main contrib non-free # For example # deb http://archive.debian.org/debian squeeze main contrib non-free Ignore check Release file…

Install ncat

# For Debian 8
$ sudo apt-get install nmap

# For Debian 10
$ sudo apt install ncat

# For Redhat based OS
$ sudo yum install nmap-ncat
# or
$ sudo dnf install nmap-ncat

Solution 1: losetup

With newer version of losetup, you can easy map parition in image file to /dev/loop*.

sudo losetup --show -Pf <imagefile>
# /dev/loop0

sudo partprobe /dev/loop0

The output will show which loop device has been mapped to image file. Now you can mount partition of it.
Example:

sudo mount /dev/loop0p1 /mnt

Create a systemd drop-in directory for the docker service

$ sudo mkdir -p /etc/systemd/system/docker.service.d