Tips And Tricks For Debian

Herbert Huffner Linux October 3, 2020

Debian is one the most widespread Linux worldwide; today, we gathered some new valuable tips about it.

1)Install:

In your computer, installed software will display the following text:

apt list --installed
dpkg-query -l

2)See Contents of a .deb file:

To see the contents of a .deb file, perform the following:

apt-get update && apt-get install apt-file
apt-file update
apt-file list [deb file]

3)add-apt-repository:

To install add-apt-repository, perform the following:

apt update
apt -y install software-properties-common dirmngr apt-transport-https lsb-release ca-certificates
add-apt-repository ppa:PPA Name]
apt update
apt install [package]

4)Repos:

Ensure dpkg-dev is installed:

apt-get install dpkg-dev

5)Create

Local

To create a local repo:

dpkg-scanpackages . /dev/null | gzip -9c > Packages.gz

Proper

To create an appropriate repo:

dpkg-scanpackages -m -a [arch] [dir] | gzip > [dir]/Packages.gz

Example

#!/bin/bash

cd /opt/shared/repo/apt

echo

for arch in i386 amd64 mips armel armhf
do	
	printf "%-10s" "${arch}:"
	dpkg-scanpackages -m -a ${arch} pool | gzip > dists/buster/main/binary-${arch}/Packages.gz
done

echo

6)trust a repo:

To trust a repo, /etc/apt/sources.list:

deb [ trusted=yes ] http://ftp.us.debian.org/debian/ jessie main contrib non-free

7)Upgrade Stretch to Buster

To upgrade from Stretch to Buster, perform the following:

apt-key adv –keyserver keyserver.ubuntu.com –recv-keys 04EE7237B7D453EC 648ACFD622F3D138
grep -rl stretch /etc/apt/ | sudo xargs sed -i ‘s/stretch/buster/g’
apt update -y && apt dist-upgrade -y
reboot

8)Creating a rootfs

To create a rootfs of Debian, perform the following

apt-get install -y qemu-user-static debootstrap binfmt-support qemu-system-arm

targetdir=rootfs
distro=buster

mkdir $targetdir
debootstrap --arch=armhf --foreign $distro $targetdir

cp /usr/bin/qemu-arm-static $targetdir/usr/bin/
cp /etc/resolv.conf $targetdir/etc

chroot $targetdir

distro=buster
export LANG=C

/debootstrap/debootstrap --second-stage

cat <<EOT > /etc/apt/sources.list
deb http://ftp.debian.org/debian $distro main contrib non-free
deb-src http://ftp.debian.org/debian $distro main contrib non-free
deb http://ftp.debian.org/debian $distro-updates main contrib non-free
deb-src http://ftp.debian.org/debian $distro-updates main contrib non-free
deb http://security.debian.org/debian-security $distro/updates main contrib non-free
deb-src http://security.debian.org/debian-security $distro/updates main contrib non-free
EOT


apt-get update -y

apt-get install -y dialog locales lsb-release nis ntp ntpdate openssh-server rsync sshfs vim

dpkg-reconfigure locales

passwd

9)chroot

ping: Address family not supported by protocol

apt-get remove -y inetutils-ping
apt-get install -y inetutils-ping

10)dnsmasq

Don’t use a dnsmasq lease file: /etc/default/dnsmasq: DNSMASQ_OPTS="--leasefile-ro"
Leases stored in /var/lib/misc/dnsmasq.leases

11)Quickies

Configure
- locale: dpkg-reconfigure locales
- Time zone: dpkg-reconfigure tzdata
Install LXDE: apt-get install task-lxde-desktop

12)RPM to Deb

To convert an rpm to a deb file, execute: alien --scripts [rpm file]

Example: alien --scripts bluejeans-1.37.22.x86_64.rpm

13)Generate Seed Files

Once a machine/VM is set up, you can generate a seed file containing the setup (be sure to install debconf-utils):

Settings from installation: debconf-get-selections --installer
Current settings: debconf-get-selections

14)Setup a Bridge

Directions

apt-get install aptitude network-manager -y
aptitude install bridge-utils
systemctl enable NetworkManager
The file /etc/network/interfaces.d/[bridge name] should resemble:

auto [bridge name]

# Bridge setup
 iface [bridge name] inet dhcp
    bridge_ports [ethernet]

As an example, a bridge named bridge0 and ethernet enp1s0:

auto bridge0

 iface bridge0 inet dhcp
    bridge_ports enp1s0

Additionally, it would be best if you also modify your etc/network/interfaces to be:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

Enable wake-on-lan

Ensure you install ethtool: apt install ethtool

auto [bridge name]

# Bridge setup
 iface [bridge name] inet dhcp
    bridge_ports [ethernet]
    /sbin/ethtool -s [ethernet] wol g

As an example, a bridge named bridge0 and ethernet enp1s0:

auto bridge0

 iface bridge0 inet dhcp
    bridge_ports enp1s0
    /sbin/ethtool -s enp1s0 wol g

15 )tftpd-hPa

If not running IPv6, /etc/default/tftpd-hpa should resemble:

# /etc/default/tftpd-hpa

TFTP_USERNAME="tftp"
TFTP_DIRECTORY="/srv/tftp"
TFTP_ADDRESS="0.0.0.0:69"
TFTP_OPTIONS="--secure -4"

The -۴ represents “use IPv4.”

All of the command we showed you on the list above is based on Debian, but here we gathered some specific order for Linux, which can come in handy when you face a problem working with Linux.

16)Add user/Addgroup

The adduser and addgroup commands let you add a new user and group to a system, respectively. Here’s an example for adduser:

$ sudo adduser testuser
Adding user `testuser' ...
Adding new group `testuser' (1003) ...
Adding new user `testuser' (1003) with group `testuser' ...
Creating home directory `/home/testuser' ...
Copying files from `/etc/skel' ...
Enter new UNIX password:

17)Cal/Local

The cal and local commands display a calendar in the output; both will show you the calendar, but there’s a slight difference, offering you the calendar differently from the other.

$ cal
March 2017 
Su Mo Tu We Th Fr Sa 
1 2 3 4 
5 6 7 8 9 10 11 
12 13 14 15 16 17 18 
19 20 21 22 23 24 25 
26 27 28 29 30 31

$ ncal
March 2017 
Su 5 12 19 26 
Mo 6 13 20 27 
Tu 7 14 21 28 
We 1 8 15 22 29 
Th 2 9 16 23 30 
Fr 3 10 17 24 31 
Sa 4 11 18 25

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