Linux Daily Learning Journey

I am learning Linux fundamentals step by step to build skills for Cloud / DevOps roles.

💻 Day 1 – linux core file systems and navigations

What I learned

-to know where AM I IN THE LINUX

• CREAT FOLDER WITH THE HELP OF MKDIR
• WITH ECHO COMAND It WILL WRITE SCRIPT
• WITH "CAT" command WE READ THE FILE

## Commands I practiced
### WHOAMI
### IS -1
### ECHO 
### CAT 
### MKDIR .

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💻 day 2 - linux permission and commands

what i have learnt in day 2 of linux journey

-i learned to create an copy of an file in the folder

• and to rename the file with comands
• how dangerous is to use rm -rf but wth caution
• learned to copy folder with cp -r and even if
• the folder is not available it will copy the actaul folder
• and try to copy the other folder when command

commands i practised for linux

mr -rf

echo$?

touch files

creating folder inside the folder

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💻 day 3 - linux ownership and permissions

what i learnt in day 3 of linux journey

• i learnt to give permission to user,group and others

• give the numerical permission such as d755 means drwxr-xr-x

• checking the server with commands

• learnt permisson types r=4,w=2,x=1

• never to use 777 numerial casually

  commands i practised today in ubuntu linux

  chmod = changing the permission

  chown = giving the ownership permission

  to check which server is running with "ps aux | grep nginx"

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# 💻 day 4 - creting user,groups and sudo and switching users

  ## what i have learnt in day 4 of liux journey

- creating users and groups and installing the service
- understanding the diffrence between normal user and sudo admin user
- sudo groups allows the user to use admin powers
- given admin access to the user which i created
- switching from main user to other user to check the permissons and access the permission



   ### commands i practised in liux networking

   ### id comand to show the user in the groups
   ### sudo usermod -aG sudo ( username )
   ### su - (user) to switch the user
   ### sudo whiami and  exit
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   # 💻 day 5 - process and sevices ( admin level)

  ## what i have learnt in day 5 of linux journey

   - process is an running system
   - to check the live monitoring
   - to kill an process
   - to force stop the process
   - service is the backgroup program
   - systemctl uses the backgrooup services
   - to stop, start , and reserat the services to
   - to check whether the service is down
   - to check top services running 
 

      ### commands i have practised
     ### ps aux | grep serive_name
    ### kill comand
    ### force kill -9 comand to kill forcefuly
    ### start service - sudo systemctl start serive-name
    ### start service - sudo systemctl stop serive-name
    ### start service - sudo systemctl restart serive-name
    ### start service - sudo systemctl disable serive-name
    ### start service - sudo systemctl enable serive-name
     ### ps aux | head
    ### q to exit the service

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  # 💻 day -6 logs and troubleshooting ( admin level )

  ## what i have learnt in day 6 linux journey
   - what logs are and where the logs stores
   - general system logs boot logs
   - real time mounitoring with the help of top
   - modern system instead of reading files
   - mountering authentication of login passwords
   - checking the terminal like usage of ram and cpu


     ## commands i practisesd hands on in ubuntu led linux        - 

     ### /var/logs here logs stored
     #### cat /var/log/auth.log shows ssh login and failed attempts
    #### /var/log/syslog it shows system back ground logs
    #### tail -f /var/log/syslog shows the real time mountering
    #### -f shows the live update of usage
    #### sudo -k its clear the chache
    #### sleep means the terminal stops working
    #### sleep & it will works in the background and we can use the terminal
    #### bg command will resume in the backgeound
    #### ctrl + z will stop the process in the terminal
    #### fg menas it will bring back the background process on the screen
    #### less shows all the process files
    #### head shows all the top 10 process
    #### tail shows the last 10 process
    #### zombie process we can't kill becasue it alredy deied we can kill the parent process or we can restart the system
    #### free -h shows the memory usage
    #### df -h shows the disk usage
    #### ps aux --sort=-%cpu | head shows the process running

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   # day 7 ssh and remote access

  ## what i have learnt in day 7 of linux journey

  ## SSH = Secure Shell Used to securely connect to a remote Linux server over a network

Default port: 22

Encrypted communication (unlike Telnet)

Remote login

File transfer

Remote command execution

Server administration

command i have practised in day 7 of linux journey

sudo systemctl status nginx

sudo systemctl start nginx

sudo systemctl stop nginx

sudo systemctl enable nginx

sudo ss -tulnp | grep nginx

its not showing my geithub commits so this is an trail