lab

 +
             +Lab 1:
    
Create ec2 vm and connect using ssh

Lab 2:

hostname
hostname -i
cat  /etc/lsb-release
ip addr
whoami
uname -a

Lab 3:
Directory command
#Create directory
mkdir test
#Change directory
cd test
#list direcotry command
ls
ls -ltr
#hidden file
ls -la
#Come out from directory
cd ..
#Check the current directory
pwd
#Trigger command for other 
ls /etc
#Check system time
date
#Read a file 
cat /etc/sudoers
#Read log file
cat /etc/sudoers
#live logs 
tail -f /var/log/dmesg

#in linux
ctrl+c
#help page
man ls
man pwd
man tail

Lab4

sudo cat /etc/sudoers
#login as superuser
sudo su
#Add 
adduser training
#It will prompt for password and info
#login as that user
su training
sudo cat /etc/sudoers
exit
exit

#delete the user
Sudo deluser amit
#Check all the user

sudo cat /etc/passwd


LAb 5

touch sample.txt # Create a file
echo "Hello World" > sample.txt
cat sample.txt
head -n 1 sample.txt
tail -n 1 sample.txt

Lab 6 
### 3. File Management
mkdir testdir
#copy the file
cp sample.txt testdir/
#renaming the file or moving the file
mv testdir/sample.txt testdir/sample-renamed.txt
#removing the file
rm testdir/sample-renamed.txt
#remvoing the directory
rm testdir/sample-renamed.txt

Lab 7

### 4. File Permissions
touch myfile
chmod 744 myfile # Set file permissions
ls -l myfile
chown $USER myfile # Change ownership
### 5. Searching Files and Text
grep root /etc/passwd # Search for 'root' in file
find /etc --name passwd # Find file named passwd
### 6. System Information
top -b -n1 | head -n 10 # View CPU usage
free -h # Show memory usage
uptime # System uptime
df -h # Disk usage
du -sh * # Disk usage by folder 


---------------
grep command

1) grep command
grep -r root /etc/
grep root /etc/passwd

grep -i root /etc/passwd

grep -i Root /etc/passwd

grep -n root /etc/passwd

grep -irn root /etc

-----------
find /etc -name passwdfind -

find /etc -name *.allow

find /etc -iname pAsswd

find /var/log/ -iname dmesg

find /etc -type d
--------------------

touch dep.yaml

ls -l dep.
chmod 400 dep.yaml
chmod 644 dep.yaml
chmod 777 dep.yaml

-------------------
chown
chown ubuntu dep.yaml
chown ubuntu:ubuntu dep.yaml
chown amit dep.yaml


-------------
sudo du /etc
sudo du -h /etc
sudo du -sh /etc

du -sh /home/ubuntu

sudo df -h

------------------

sudo su


-------------------------------------

09/06

Lab1

open a file using vi editor:
    
vi test

To go in insert mode press i

Then type following

Line1
Line2
Line3

Go to the normal mode while press esc key

To save and exit from the file you will press :wq


Lab2: Don;t want to save the latest change

vi test

Press "i" to enable the insert mode

Add few line

Line1
Line2                                                                                                                                                                                         
Line3

Line4
Line5   
I don't want save latest changes

esc :q!


Lab3:
    

sudo vi /etc/sudoers

Press "i" ,and type below new line

# new code

Try to save that file esc+:wq

it will give a error read only file,

When you want to override readonly file

esc+:wq!

Lab4

vi test

Line1
Line2
Line3

COpy the line3, take the cursor to that line using keyboard, then press"yy"

whereever you want to paste, press "p"

esc+ :wq

vi test

Line1
Line2
Line3

Cut the line3, take the cursor to that line using keyboard, then press"dd"

whereever you want to paste, press "p"

esc+:wq


Lab 5


sudo apt update

sudo yum update

sudo dnf update

you want to install java

sudo apt-get install openjdk-17-jdk

sudo yum install openjdk-17-jdk

sudo dnf instalal openjdk-17-jdk

Lab 6:

Install this package "docker-ce"

 You can use a shebang to tell Linux which interpreter is needed to run the script


Lab 7:
    
vi test.sh

ls
date
apt-g
et update
save the file esc+:wq

./test.sh

It will give error, read write but no excute writes

chmod +x test.sh

ls -l test.sh

./test.sh

--------------------------------------------------


Go and write the script to install  vim

#!/bin/bash
sudo apt-get update
sudo apt-get install vim -y

Write a shell script to find a file "passwd" in /etc directory

vi filesearch.sh 
Press i to enable insert mode
Copy and  paste two line code below mentioned
#!/bin/bash
find /etc/ -name passwd
save file  esc :wq
chmod for execution rithts
 chmod +x vim.sh
./vim.sh

-------------------
Write a code to find the error message in /var/log

#!/bin/bash
grep -ir error /var/log

----------------------------------
11/06

Lab1: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/linux-file-transfer-scp.html


LAb2

dpkg -s apache2
dpkg -s apache2 &> /dev/null
echo $?


vi test.sh
#Copy the below code
chmod +x

    fi
fi

#Save the code

chmod +x test.sh
./test.sh
dpkg -s apache2
dpkg -s apache2 &> /dev/null
echo $?


Lab3:
vi checkpack.sh
#!/bin/bash

# Function to check and install a package
install_package() {
    local package_name=$1

    if dpkg -s "$package_name" &> /dev/null; then
        echo "$package_name is already installed. ✅ Success"
    else
        echo "$package_name not found. Installing..."
        sudo apt update && sudo apt install -y "$package_name"
        if [ $? -eq 0 ]; then
            echo "$package_name installed successfully. ✅ Success"
        else
            echo "$package_name installation failed. ❌"
        fi
    fi
}

# Ask user for package name
read -p "Enter the package name you want to install: " pkg
install_package "$pkg"


chmod +x checkpack.sh

./checkpack.sh


Lab 4

#!/bin/bash

# Function 1: Check if the package is already installed
is_installed() {
    local package=$

1
    dpkg -s "$package" &> /dev/null
    return $?
}

# Function 2: Check if the package is available in the remote apt repository
is_installed() {
    local package=$1
    dpkg -s "$package" &> /dev/null
    return $?
}


# Function 3: Install the package if not installed and available
install_package() {
    local package=$1

    if is_installed "$package"; then
        echo "$package is already installed. ✅"
    else
        echo "$package is not installed. Checking availability in the repo..."
        if is_available_in_repo "$package"; then
            echo "$package is available. Installing..."
            sudo apt update && sudo apt install -y "$package"
            if [ $? -eq 0 ]; then
                echo "$package installed successfully. ✅"
            else
                   echo "Failed to install $package. ❌"
            fi
        else
            echo "$package is not available in the repository. ❌"
        fi
    fi
}

# Read multiple package names from user (space-separated)
read -p "Enter package names (space-separated): " -a packages

# Loop through all provided package names
for pkg in "${packages[@]}"; do
    echo "-----------------------------"
    echo "Processing: $pkg"
    install_package "$pkg"
    echo "-----------------------------"
done


-------------------------------------------------------------
12/06
Lab1
1) 
git --version
mkdir test
cd test
git status
#It will give error not a git repository
ls -la
#check any .git subdirectory is there or not
git init
ls -la
git status
#Check error message not a git diretory is coming or not

---------------------------
Lab2:
git config --global user.name  "Your Name"
git config --global user.name "yourname@example.com"
---------------------
Lab3:
touch code
git status
#Untracked file
git add code
git status
#Changes to comitted message come
touch code1
git add code1
git status
-----------------------------------
Lab 4:

git commit -m "addingcode"
git status
git log
git reflog
git show <commit id from reflog>
example
git show 48010e2

https://www.openwriteup.com/?page_id=1075
https://www.openwriteup.com/?page_id=1081

-------------------------------------------------

Lab 5

vi code
#!/bin/bash
date

Save the file

git add code
git commit -m "changing"
git status
git log
git reflog
git diff <id1> <id2>
#example
 git diff 693431c a96635b


---
ssh-keygen -t rsa

cat  /home/ubuntu/.ssh/id_rsa.pub


----------------------------------------------------------------------------------------------------------------------------------------------------
16/06
#How to initate the git repo
mkdir test
cd test
git status
git init
cd ..
#If you are goin
git statusg outside from that directory, you are going out of scope 
git status
cd test
--------------------
Lab2
git config --global user.name amit
git config --global user.email amit@ow.com
git config --global --list
touch codefile
git add codefile
git status
git commit -m "adding"
git log
git reflog
---------------------------
git reflog
git show commitid
#for example
                    

-------------------------
vi codefile
#!/bin/bash
echo "hell"

git add .
git commit -m "add"
git reflog

--------------------
Lab 4
cat .git/configg
#Copy the git remote command from github.com
git remote add origin url
cat .git/config

git branch
git branch -M main
git branch

------------------
git push -u origin main


ssh-keygen -t rsa

cat  /home/ubuntu/.ssh/id_rsa.pub

-----------------
Try this

pwd
touch newcode
mkdir newdir
touch newdir/file
git add .
git commit -m "changes done"
git push -u origin main

#Check your github repo
git log
git status
git reflog






--------------

18/06


git clone https://github.com/amitopenwriteup/java11-examples.git

#Downloading the latest package defination

sudo apt-get update

#Installing the java

sudo apt-get install openjdk-17-jdk -y

#Install maven
sudo apt-get install maven -y

cd java11-examples
mvn clean package
#Check for jar file
ls target/