Remote GUI from Ubuntu

sudo apt purge ubuntu-desktop
sudo systemctl disable --now gdm
systemctl set-default multi-user.target

To enable the GUI again:

systemctl set-default graphical.target

Computername and other info

hostnamectl

To chance computer name

hostnamectl set-hostname {name-here}
vi /etc/hosts #Replace the old name for the new one here

Computer Uptime

uptime

CPU Info

lscpu

Task Manager

Deb Version

wget https://github.com/cjbassi/gotop/releases/download/3.0.0/gotop_3.0.0_linux_amd64.deb
sudo dpkg -i gotop_3.0.0_linux_amd64.deb

or RPM Version

wget https://github.com/cjbassi/gotop/releases/download/3.0.0/gotop_3.0.0_linux_amd64.rpm
sudo rpm -ivh gotop_3.0.0_linux_amd64.rpm

List PCI Network Devices

lspci  
# Look between those lines for the NIC. vm = Intel Corporation 82xxxx

Full System Info

sudo lshw
lsshow -html > systeminfo.html

Start/Stop/Restart a Service

systemctl list-unit-files --type service -all
systemctl list-unit-files --no-pager
systemctl | grep running
systemctl start service name
systemctl stop service name
systemctl restart service name
sudo systemctl disable name
sudo systemctl enable --now name
systemctl status name

Kill a Process

Identify the process of the App top
Find the PID: via TOP

then

killall 9

where the next number is the PID, to close

or

Find the PID: via ps -ef | grep appname

kill 9

or

If using GUI, then xkill then click over the app to close

Mute Volume

amixer set Master muteclear

Linux Installed OS version

lsb_release -a

Overview Configuration

sudo -i

Name of the type of Drive(s) being used

dmesg| grep sd

Check to see for Mounted Drives

mount

to Reload Mounts

sudo mount -a

if Debian for how much space on HDD(s), even USB, (on the for line will tell you the Mount Drive name)

df -h --total

or

df -h --total | grep total

or

df -h --total | sed '4!d

or a better view with JSON output

wget https://github.com/muesli/duf/releases/download/v0.6.0/duf_0.6.0_linux_amd64.deb
dpkg -i duf_0.6.0_linux_amd64.deb
duf

last reboots

last reboot

Dates

cal

or with current Time

date

Whos is logged In

or current

whoami

Running Processes

ps

Apps Installed by their used space

#!/bin/sh    
    
dpkg-query --show --showformat='${Package}\t${Installed-size}\t${Status}\n' |    
    awk '    
{    
    # evaluate installed packages only
    if($3 == "install"){    
        packages[$1] = $2    
    }    
}    
    
END {    
    # sort packages by size (change 'asc' to 'desc' to reverse the order)
    PROCINFO["sorted_in"] = "@val_num_asc"
    for (i in packages){    
        printf "%05.2fM | %s\n",
        packages[i] / 1024, # convert from kilobytes to megabytes
        i    
    }    
}    
'

Find Out how Memory Dets

vmstat -s

or

free -h

CPU Being Used

cat /proc/cpuinfo

Current

hostname -I

Ports using specific Ports

sudo lsof -P -i:631

List all the porta that are active with what peer

sudo ss -tulwnp

Interfaces Devices

ip link show

OR

nmcli device status

OR

/sbin/ifconfig -a

Check for all the MAC address your device around the network, try to ping the device if stil doesn't show up

It works better on Windows

sudo apt install net-toolsc
arp -a

Renew an IP address

sudo dhclient -r
sudo dhclient

DEB, check for Updates/Upgrades

sudo apt update && sudo apt upgrade -y

afterwards

sudo apt autoremove

Check Version for Pi-Hole

pihole -v

Display specific lines from a file

tail -3 /var/log/cups/access_log

Display the User's Group

id

Create a new user and his Home DIR

useradd -c "John Doe" -m john

Delete the user

userdel john

#Add the User to a group

usermod -aG sales john

Create a shortcut

ln -s /path/to/file linkname

Locating files

apt install mlocate
locate file.txt

Location Path

pstree

Change Prompt

PS1="[ ${debian_chroot:+($debian_chroot)}\u is awesome: \w ]\\$ "

Create an Empty File

touch fileName

#Read a txt file

less file

History

history

Rename file

mv fileA fileB

Update Pi-Hole

pihole -up

Router Table

ip r

Internet Gateway

ip r | grep ^def

# SSH

ssh username@IpAddress

**yes** </br>
then type in the _password_ for the host </br>

Check for status </br>

sudo service ssh status


# Static IP Address
GUI Method
![image](https://user-images.githubusercontent.com/44326428/128663929-34a42601-7c0f-4e9e-b503-4558dc3bbf2f.png)

# Restart

systemctl reboot -i


# TracerRoute for Ubuntu
```RUBY
sudo apt install inetutils-traceroute
sudo apt install traceroute

Ping for a count of 3

ping -c 3 google.com

Show Programs using the network

netstat -nutlp

Renew or Release IP

Deb

systemctl restart network.service

or RPMs

systemctl restart networking.service

Assign a Static IPv4 Address.

Back up your current network configuration:

sudo cp /etc/netplan/00-installer-config.yaml /etc/netplan/00-installer-config.yaml.bak

Find your Interface with ip a in this case is enp0s3 but it could be epns08... then adjust the code below

network:
  version: 2
  renderer: networkd
  ethernets:
    enp0s3:
      dhcp4: no
      addresses: [192.168.1.2/24]
      gateway4: 192.168.1.1
      nameservers:
        addresses: [8.8.8.8, 8.8.4.4]

save it with : press Ctrl + X while you could refresh it with sudo netplan apply is recommended to just restart hence you might be connected via SSH anyways

Get an IP from a DNS

dig google.com

Download a file

wget https://gdlp01.c-wss.com/gds/0/0300004730/02/eosrt3-eos1100d-im2-c-en.pdf

File / Folder properties

ls -all file.txt
ls -lh file.txt
ls -all folder

8 Permissions: r=Read ; w=Write ; x=Execute

Installing a Samba share

sudo apt install samba -y

Create a folder destined to do the SHARE , 👉change your path

mkdir /home/USERNAME/Desktop/sambashare/

Configure it sudo nano /etc/samba/smb.conf
At the end of the file add this, 👉 But make your required changes to your path: , then save it

[sambashare]
    comment = Samba on Ubuntu
    path = /home/adam/Desktop/sambashare/
    read only = no
    browsable = yes

Restart and Allow the Firewall

sudo service smbd restart
sudo ufw allow samba

Create the Username and then it will ask you to add a password for the SAMBA

sudo smbpasswd -a USER-NAME-GOESHERE

To connect to it, if Linux/Mac smb://ipaddress/sambashare or Windows \\ipaddress\sambashare

Find file which sizes are between 5-10MB

sudo  find / -size +5M -size -10M

Find all files which are accessed N days back

find / -atime 2

Find modifies files in the last N minutes

find / -mmin -1

JSON Utility

sudo apt install jshon -y
echo '{"name": "Kesk","surname":"norem"}' | jshon
echo '{"name": "Kesk","surname":"norem"}' | jshon > file.json

TAR (Compression) - tar -czvf name_of_file_to_be.tar.gz then the actual file

tar -czvf eosManual.tar.gz eosrt3-eos1100d-im2-c-en.pdf

Multiple folders & Files

tar -czvf file.tar.gz /home/user1/ /home/user2/

you can also exclude a folder ie.

tar -czvf archive.tar.gz /home/user1 --exclude=*.mp3

To Extract file in same directory

tar -xzvf eosManual.tar.gz

To Extract file in different directory

tar -xzvf eosManual.tar.gz -C folder2/

ZIP a file

Prerequisites:

sudo apt install zip unzip

Name of the file that will be, then the actual filename, Example:

zip eosrt3-eos1100d-im2-c-en.zip  eosrt3-eos1100d-im2-c-en.pdf

To Zip many Files & Folders

zip -r Manuals.zip eosrt3-eos1100d-im2-c-en.pdf folderWfiles

To Unzip

unzip Manuals.zip

Send Files

scp file.pkg remote_username@10.10.0.2:/remote/directory

Remove Folders (for a single file don't use the 'rf')

rm -rf folderWfiles/

Creating a script

nano Downloads/runner.sh

Content of a simple script:

#!/bin/bash
echo "Computer Name: "  $(hostname) > Downloads/filelist.txt
echo " "
ls                                 >> Downloads/filelist.txt
echo "Today's Date: "  $(date)     >> Downloads/filelist.txt

Making it Executable

sudo chmod 774 Downloads/runner.sh

Execution: ./Downloads/runner.sh

Deploying a script (only works from another Linux)

Method 1: Via Line by Line:

ssh useradmin@10.10.10.10 'bash -s' <<'ENDSCRIPT'
echo "Computer Name: "  $(hostname) > Downloads/filelist.txt
echo " "
ls                                 >> Downloads/filelist.txt
echo "Today's Date: "  $(date)     >> Downloads/filelist.txt
ENDSCRIPT

Method 2: Via a script written in local:

ssh useradmin@10.10.10.10 'bash -s' < runner.sh

Maniuplating Text:

quotes.txt

The present is theirs; the future, for which I really worked, is mine.
Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more.
The day science begins to study non-physical phenomena, it will make more progress in one decade than in all the previous centuries of its existence

-Nikola Tesla

Picking and Highlighting specific word(s):

grep "virtues" quotes.txt

Picking and Highlighting specific word(s), while guessing char(s)

grep "virt[a-z][a-z]" quotes.txt

Replacing specific word(s)

sed -i 's/I really worked/I really did not worked/g' quotes.txt

Convert Lower Case

sed -e 's/\(.*\)/\L\1/' hello.txt > output.txt

Toast Notification

#!/bin/bash
sleep 10
notify-send "notify.sh" "Task complete successfully"

Text Styles

#!/bin/bash
bold=$(tput bold)
underline=$(tput smul)
italic=$(tput sitm)
info=$(tput setaf 2)
error=$(tput setaf 160)
warn=$(tput setaf 214)
reset=$(tput sgr0)
echo "${info}INFO${reset}: This is an ${bold}info${reset} message"
echo "${error}ERROR${reset}: This is an ${underline}error${reset} message"
echo "${warn}WARN${reset}: This is a ${italic}warning${reset} message"

Multitasking

#!/bin/bash
function task1() {
    echo "Running task1..."
    sleep 5
}
function task2() {
    echo "Running task2..."
    sleep 5
}
task1 &
task2 &
wait
echo "All done!"

For Loops

While Loop

#!/bin/bash
while true;
do
    # Frame #1
    printf "\r< Loading..." 
    sleep 0.5
    # Frame #2 
    printf "\r> Loading..." 
    sleep 0.5 
done

Loops

Example 1

for i in 3 43 44 11 9; do echo $i; done

Example 2

#!/bin/bash
for i in {1..10}
do
  echo "Thi is line: " $i
done

chmod +x looper.sh
./looper.sh

File Exist

if [[ -f file ]]; then echo "exits"; else echo "doesn't exit"; fi

Folder Exist

if [[ -d folder ]]; then echo "exits"; else echo "doesn't exit"; fi

Fix Ubuntu partitions, showing small size:

sudo lvextend --resizefs -l +100%FREE ubuntu-vg/ubuntu-lv

Intalling NALA , GUI replacement for `apt`

sudo apt install nala

Directory Folders Content

 ```Ruby

Folder	Content
/.	Root Directory for every directory. Read/Write Only unlesss Sudo access
/	Everything on your Linux system is located under the / directory
/bin -> /usr/bin	Contains the essential user binaries (programs) that must be present when the system is mounted in single-user mode
/boot	The startup files and the kernel, vmlinuz. In some recent distributions also grub data. Grub is the GRand Unified Boot loader and is an attempt to get rid of the many different boot-loaders we know today.
/dev	directory contains a number of special files that represent devices. These are not actual files as we know them, but they appear as files — for example, /dev/sda represents the first SATA drive in the system. If you wanted to partition it, you could start a partition editor and tell it to edit /dev/sda, /dev/random produces random numbers.
/etc	Most important system configuration files are in /etc, this directory contains data similar to those in the Control Panel in Windows
/home	Home directories of the common users.
/lib -> /usr/lib	The /lib directory contains libraries needed by the essential binaries in the /bin and /sbin folder. Libraries needed by the binaries in the /usr/bin folder are located in /usr/lib
/lib64 -> /usr/lib64	Directory containing 64-bit system libraries.
/media	contains subdirectories where removable media devices inserted into the computer are mounted
/mnt	Directory used for temporarily mounting remote filesystems and other media
/opt	contains subdirectories for optional software packages
/proc	/proc directory similar to the /dev directory because it doesn’t contain standard files. It contains special files that represent system and process information
/root	The root user's home directory.
/run	A runtime scratch directory (RAM-based).
/sbin -> /usr/sbin	The /sbin directory is similar to the /bin directory. It contains essential binaries that are generally intended to be run by the root user for system administration
/selinux	If your Linux distribution uses SELinux for security (Fedora and Red Hat, for example), the /selinux directory contains special files used by SELinux. It’s similar to /proc. Ubuntu doesn’t use SELinux, so the presence of this folder on Ubuntu appears to be a bug
/srv	Contains “data for services provided by the system.” If you were using the Apache HTTP server to serve a website, you’d likely store your website’s files in a directory inside the /srv directory
/sys	Directory containing devices, kernel modules, filesystems, and other kernel component info
/tmp	Temporary space for use by the system, cleaned upon reboot
/usr	Programs, libraries, documentation etc. for all user-related programs.
/var	Variable data files are stored here. This can include things like log files, MySQL, and other database files, web server data files, email inboxes, and much more.

At the Scripting level

https://devhints.io/bash

In case of error such repos cannot be found or problems upgrading:

Resolution 1 (Prefered to test first)

ie. The repository 'http://archive.ubuntu.com/ubuntu kinetic Release' no longer has a Release file.
sudo nano /etc/apt/sources.list and add "old-", to the hyperlinks shown there. something like:
http://old-releases.ubuntu.com
then save the file and do do-release-upgrade this will revamp the next possible version and then run the progress

Resolution 2 - (In case Resolution 1 Fails)

Back up you main repo file sudo cp /etc/apt/sources.list /etc/apt/sources.bak
findout what is the current version of Ubuntu Install hostnamectl then check in the ubuntu.com website what is the name codename
Edit the same sudo nano /etc/apt/sources.list
Replace the prior version with the new version: ^ \ in this example: kinetic for lunar (check every entry)
sudo apt update -y
sudo apt upgrade -y
If prompted to configure libc6 to restart services. Tab over to “yes” and hit ENTER.
Select all services (check with your other apps as this will be restarted, specially if this a PROD enviroment)
sudo apt dist-upgrade -y
You might get prompted to select your language twice
sudo apt dist-upgrade -y
you might need to remove all libraries sudo apt autoremove
sudo reboot
check again and see if it is already upgraded hostnamectl
at this point the platform for that version now should be ready for the next do-release-upgrade
follow prompts., 🍵time and walk it off this part will take a while.
Enjoy! 😉

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Folders and files

Latest commit

History

Repository files navigation

Remote GUI from Ubuntu

Computername and other info

To chance computer name

Computer Uptime

CPU Info

Task Manager

List PCI Network Devices

Full System Info

Start/Stop/Restart a Service

Kill a Process

Mute Volume

Linux Installed OS version

Overview Configuration

Name of the type of Drive(s) being used

Check to see for Mounted Drives

if Debian for how much space on HDD(s), even USB, (on the for line will tell you the Mount Drive name)

last reboots

Dates

Whos is logged In

Running Processes

Apps Installed by their used space

Find Out how Memory Dets

CPU Being Used

Current

Ports using specific Ports

List all the porta that are active with what peer

Interfaces Devices

Check for all the MAC address your device around the network, try to ping the device if stil doesn't show up

Renew an IP address

DEB, check for Updates/Upgrades

Check Version for Pi-Hole

Display specific lines from a file

Display the User's Group

Create a new user and his Home DIR

Delete the user

Create a shortcut

Locating files

Location Path

Change Prompt

Create an Empty File

History

Rename file

Update Pi-Hole

Router Table

Internet Gateway

Ping for a count of 3

Show Programs using the network

Renew or Release IP

Assign a Static IPv4 Address.

Get an IP from a DNS

Download a file

File / Folder properties

Installing a Samba share

Find file which sizes are between 5-10MB

Find all files which are accessed N days back

Find modifies files in the last N minutes

JSON Utility

TAR (Compression) - tar -czvf name_of_file_to_be.tar.gz then the actual file

ZIP a file

Send Files

Remove Folders (for a single file don't use the 'rf')

Creating a script

Deploying a script (only works from another Linux)

Maniuplating Text:

Multitasking

For Loops

Loops

File Exist

Folder Exist

Fix Ubuntu partitions, showing small size:

Intalling NALA , GUI replacement for apt

Directory Folders Content

At the Scripting level

In case of error such repos cannot be found or problems upgrading:

Resolution 1 (Prefered to test first)

Intalling NALA , GUI replacement for `apt`

Packages