Cheat sheets

timedatectl list-timezones

sudo timedatectl set-timezone Europe/Paris

sudo hostnamectl set-hostname [new_name]

sudo vim /etc/netplan/01-cfg-ens19.yaml
network:
    ethernets:
    ens19:
        addresses:
        - 172.16.0.1/12
    version: 2
sudo chmod 600 /etc/netplan/*
sudo netplan apply

nmcli connection show
NAME          UUID                                  TYPE      DEVICE
 WiFi5      79361210-59bd-4a91-a4af-c78634446295  wifi      wlp2s0

nmcli connection modify “Wired connection 1” connection.interface-name “ens19”

nmcli con mod <NET_UUID> ipv4.address 192.168.1.2/24
nmcli con mod <NET_UUID> ipv4.gateway 192.168.1.1
nmcli con mod <NET_UUID> ipv4.method manual
nmcli con mod <NET_UUID> ipv4.dns 8.8.8.8
nmcli con mod <NET_UUID> autoconnect yes
nmcli con down <NET_UUID>
nmcli con up <NET_UUID>

ls -alrt
-rwxrwxr–. 1 ansible automation 4 Nov 13 10:57 helloworld.txt

r = read = 4
w = write = 2
x = execute = 1
[ user = u ] [ group = g ] [ others = o ]
The user ansible has 4+2+1=7 (full access)
The group automation has 4+2+1=7 (full access)
All others have 4  (read-only)

chmod 644 myfile

chown -R user:group /mydirectory/

$ sudo fdisk -l /dev/nvme*

# check free space
sudo fdisk -l
# Extend physical drive partition
sudo growpart /dev/sda 3 
# See  phisical drive
sudo pvdisplay
# Instruct LVM that disk size has changed
sudo pvresize /dev/sda3

# View starting LV
sudo lvdisplay
# Resize LV
sudo lvextend  -l +100%FREE /dev/ubuntu-vg/ubuntu-lv
df -h
#Resize Filesystem
sudo resize2fs /dev/mapper/ubuntu–vg-ubuntu–lv

fdisk /dev/sdc
Command (m for help): n and enter
Command (m for help): w

mkfs.ext4 /dev/xvdc1

sudo apt-get install samba
sudo smbpasswd -a denis
sudo vim /etc/samba/smb.conf
[data]
   path = [folder_to_share]
   valid users = [user]
   read only = no
   # guest ok = yes # no auth
sudo systemctl restart smbd
sudo systemctl enable smbd

$ cd /etc/systemd/network/
$ sudo touch vbr0.netdev vbr0.network

$ sudo vim vbr0.netdev
[NetDev]
Name=vbr0
Kind=dummy

$ vim vbr0.network
 [Match]
Name=vbr0
[Network]
Address=172.16.0.249
Mask=255.240.0.0
Broadcast=172.31.255.255

$ sudo systemctl restart systemd-networkd
$ sudo systemctl enable systemd-networkd

lsb_release -a

sudo apt install vim net-tools htop vlc
sudo snap install jdownloader2

sudo apt install openssh-server -y
Edit /etc/ssh/sshd_config
PasswordAuthentication yes
sudo systemctl restart ssh

https://etcher.balena.io/#download-etcher

sudo apt-get install xrdp
sudo systemctl enable xrdp
sudo adduser xrdp ssl-cert
add setxkbmap fr to $HOME/.profile

DesktopVer="$XDG_CURRENT_DESKTOP"
SessionVer="$GNOME_SHELL_SESSION_MODE"
ConfDir="$XDG_DATA_DIRS"
sudo sed -i “4 a #Improved Look n Feel Method\ncat «EOF > ~/.xsessionrc\n
export GNOME_SHELL_SESSION_MODE=$SessionVer\nexport XDG_CURRENT_DESKTOP=$DesktopVer\n
export XDG_DATA_DIRS=$ConfDir\nEOF\n” /etc/xrdp/startwm.sh

sudo vim /etc/gdm3/custom.conf
AutomaticLoginEnable=false

sudo systemctl disable systemd-resolved.service
sudo systemctl stop systemd-resolved

$ sudo vim /etc/NetworkManager/NetworkManager.conf
dns=default

$ sudo rm /etc/resolv.conf
$ sudo systemctl restart NetworkManager.service

sudo pkill -9 -u denis

ssh-keygen -b 4096

ssh-copy-id username@remote_host

sudo nano /etc/ssh/sshd_config
PermitRootLogin no
sudo service sshd restart

sudo nano /etc/ssh/sshd_config
PasswordAuthentication no
sudo service sshd restart

sudo apt install git

git config –global user.name <USER_NAME>
git config –global user.email <USER_EMAIL>

git config –global commit.gpgsign true
git config –global user.signingkey <KEY_ID>

gpg –list-secret-keys –keyid-format=long
sec   rsa4096/<KEY_ID> 2021-06-09 [SC]

gpg –full-generate-key

gpg –edit-key <KEY_ID>

gpg –import “gpg_private.key”

gpg –armor –export <KEY_ID>—–BEGIN PGP PUBLIC KEY BLOCK—–
mQINBGDBBhIBEADD/m4EK+XFiW20rE8fhLgom+zI/eExjaTUbLrLPj2q6SxxX2rg
…
mQINBGDBBhIBEADD/m4EK+XFiW20rE8fhLgom+zI/eExjaTUbLrLPj2q6SxxX2rg
—–END PGP PUBLIC KEY BLOCK—–

:g/<REGEX_PATTERN>/d

sudo apt install sqlite3
wget [github_url_pdns]/master/modules/gsqlite3backend/schema.sqlite3.sql
sqlite3 pdns.db
.read schema.sqlite3.sql
.quit

sudo docker compose exec pdns pdnsutil list-all-zones

sudo docker compose exec pdns pdnsutil create-zone home.

pdnsutil add-record home. ns1 A 3600 172.16.0.253
New rrset:
ns1.home. 3600 IN A 172.16.0.253

pdnsutil replace-rrset home. test A 3600 192.168.1.253
Current records for test.home IN A will be replaced
New rrset:
test.home. 3600 IN A 192.168.1.253