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Husband πŸ‘©β€β€οΈβ€πŸ‘¨ | Father πŸ‘ͺ | DevOpsπŸ’» | Hashnode πŸ‘©β€πŸ’» https://t.co/sZZFQnS8RQ | Medium ⭐ https://t.co/8DnlXlE1No | Content CreatorπŸ“| About me 😎 https://t.co/qp6Je2lYEE
30 Nov
What is systemd and why should Linux users care about it?

Everything about "systemd" !!

A Mega Thread πŸ‘‡ https://everyday.codes/
What is systemd ?

systemd is the glue that holds Linux systems together. systemd is a collection of building blocks, which handle services, processes, logging, network connectivity and even authentication. PC: https://images.techhive.com/ & ZDNet
systemd handles the boot process for Linux systems. As an init implementation, it has a PID of 1 like other init systems, such as System V, Upstart.

It was designed as a replacement for SystemV and LSB-style startup scrips, which were prevalent since 1980s.
Read 44 tweets
19 Nov
#Linux Boot Process Explained!

A Thread πŸ‘‡ PC: https://images.wallpapersden.com/
Every Linux Admin or DevOps Engineer should know what happens when a Linux system boots. It's a very popular Interview Question as well.
Every time you power on your Linux PC, it goes through a series of stages before finally displaying a login screen that prompts for your username or password.

There are 3 high level stages of a typical Linux boot process.
Read 20 tweets
29 Oct
Everything you need to know about Virtualization, VMs , Containers, Pods, Clusters ..

A Mega Thread πŸ‘‡ PC: production-cci-com.imgix.net
What is Virtualization?

Virtualization is the act of dividing shared computational resources: CPU, RAM, Disk, and Networking into isolated resources that are unaware of the original shared scope. PC: cloud4y
What is a virtual machine?

A VM is a virtual env that functions as a virtual computer system with its own CPU, memory, nw interface, & storage, created on a physical hw system (located off- or on-prem).

It uses sw instead of a physical computer to run programs & deploy apps. PC: nakivo
Read 26 tweets
27 Oct
Traceroute: A computer Network Diagnostic Tool πŸ› οΈ

How does it work! πŸ€”

Ping works fine but not traceroute! 🀨

What are the stars in traceroute output! *⃣*⃣*⃣

#Linux #Networking

A Thread πŸ‘‡ PC: n-able.com
What is traceroute ?

traceroute tracks the route packets take across an IP network on their way to a given host.

It assists you in troubleshooting nw connectivity issues from your Destination to a Remote destination by using echo packets (ICMP) to visually trace the route.
The syntax -

The cmd traceroute <x> (x here being an IP or hostname) is d most basic version & it will begin to send packets to d designated target. This result will allow u to trace d path of d packets sent from ur machine to each of d systems b/n u & ur desired destination.
Read 22 tweets
25 Oct
Cyber Security Basics!

#infosec

A Mega Thread πŸ‘‡ PC: cyberoregon
What is Cyber Security?

Cybersecurity is a way of protecting the network, computers, and other electronic gadgets from cybercriminals. The Malicious attackers might delete, modify or leak confidential information posing a huge threat to a business or an individual. PC: abacustechnologies
What is Cyber Crime?

Here are some examples of Cyber Crime:

1. Identity Theft

2. Online Predators

3. BEC ("Business Email Compromise")

4. Ransomware

4. Stealing of sensitive intellectual property
Read 33 tweets
22 Oct
What is Kubernetes and How it works!

A Short Thread πŸ‘‡πŸ‘‡ Image
Use case ->

You have created an application and want to share it with the world. Image
Docker comes into the picture to package the application. Image
Read 10 tweets
18 Oct
Securing Linux Servers!

Everything about Iptables - The Linux Firewall.

#infosec

A Mega Thread πŸ‘‡
Iptables is a command-line firewall utility for Linux. It monitors traffic from & to ur server using tables.
These tables contain sets of rules, called chains, that will filter incoming & outgoing data packets. PC: linuxkamarada
When someone tries to establish connection to and from your system iptables immediately looks for a rule in its list to match it and If it doesn’t find a matching one, it resorts to the default action (either DROP or Accept).
Read 45 tweets
13 Oct
Copying files and directories remotely.

Keeping Linux files and directories in sync.

Everything about "rsync"

A Thread πŸ‘‡
What Is Rsync?

Rsync, or Remote Sync, is a fast, versatile and free command-line tool that lets you transfer and sync files and directories to local and remote destinations in an efficient and secure way. .
Why use Rsync?

When copying or moving large no. of files using tools like cp and mv may leave ur data in inconsistent state with part of it still in the original location and part of it in the target destination in case of any interruptions.
Read 29 tweets
9 Oct
These days we are hearing a lot about #web3.

What's that?

A short thread πŸ‘‡
What was web1 or web?
The very first stage of development on the World Wide Web where only simple static websites used to exist.

Those were the times when Personal web pages (mostly static pages) used to be hosted on ISP-run web servers, or on free web hosting services.
What is web2?

Today's internet is all about web2. As per @Wikipedia Web 2.0 refers to websites that emphasize user-generated content, ease of use, participatory culture and interoperability for end users where websites and apps allow anyone to create content and share.
Read 5 tweets
9 Oct
Kubernetes security best practices in short -

A Thread πŸ‘‡ PC: Threat Stack
1. Keep the Kubernetes cluster up to date.
2. Ensure That Only Authorized Images are Used in Your Environment
3. Limit Direct Access to Kubernetes Nodes
4. Create Administrative Boundaries between Resources
5. Keep Secrets Secret!
6. Define Resource Quota
7. Implement Network Segmentation
8. Apply Security Context to Your Pods and Containers
9. Restrict API access.
10. Restrict SSH access.
Read 6 tweets
9 Oct
Linux Networking Tools -

ss, nmap, dig, netcat, ping, tcpdump, socat, top, ethtool

A Thread πŸ‘‡
SS -

ss command is a tool that is used for displaying network socket related information on a Linux system.
nmap -

Nmap is short for Network Mapper. It is an open-source Linux cmd-line tool that is used to scan IPs & ports in a nw & to detect installed apps. Nmap allows nw admins to find which devices r running on their nw, discover open ports & services, and detect vulnerabilities.
Read 12 tweets
7 Oct
SSL Decoded!

Everything you need to know about Secure Socket Layer.

A Thread πŸ‘‡
What is SSL ?

It’s a protocol for encrypting and securing communications that take place on the Internet. It's now replaced by an updated protocol called TLS (Transport Layer Security) some time ago.
The main use case for SSL/TLS is securing communications between a client and a server, but it can also secure email, VoIP, and other communications over unsecured networks.
Read 23 tweets
7 Oct
I rarely use password login. And many folks out there even today aren't sure about ssh keys and their usage.

Everything about SSH Keys.

A Thread πŸ‘‡
What is SSH?

SSH is a secure protocol used as the primary means of connecting to Linux servers remotely. It provides a text-based interface by spawning a remote shell. After connecting, all commands you type in your local terminal are sent to d remote server and executed there.
Today, the SSH protocol is widely used to login remotely from one system into another, and its strong encryption makes it ideal to carry out tasks such as issuing remote commands and remotely managing network infrastructure and other vital system components.
Read 27 tweets
5 Oct
Python Cheat Sheet πŸ‘‡
Part - 1 Image
Part -2 Image
Read 4 tweets
5 Oct
BGP - A possible reason behind the recent disappearance of #facebook #instagram & #whatsapp from the internet.

What is BGP ?

#facebookoutage #networking

A Thread πŸ‘‡
BGP (Border Gateway Protocol) is the routing method that enables the Internet to function. Without it, we wouldn’t be able to do a Google search or send an email. Image
What is network routing?

β€œThe name of a resource indicates what we seek, an address indicates where it is, and a route tells us how to get there”.

- John F. Shoch
Read 14 tweets
4 Oct
Why I Love BASH?

Everything about Bourne again shell (BASH)!

A pictorial thread πŸ‘‡
Why I love bash? Image
BASH Input. Image
Read 20 tweets
27 Sep
What is Git?

What is GitHub?

Learn Git in just one thread! πŸ‘‡
What is Git?

Git is a free, open-source distributed version control system. It keeps track of projects and files as they change over time with the help of different contributors.

A very popular tool used for source code management.
What is GitHub ?

GitHub is an online Git repository hosting service. Thought It adds many of its own features. While Git is a command line tool, GitHub provides a Web-based graphical interface.
Read 53 tweets
25 Sep
What is CPU Load Average?

#Linux #DevOps #Compute

A thread πŸ‘‡
Load averages are the three numbers shown with the uptime and top commands - they look like this:

load average: 0.09, 0.05, 0.01 Image
The three numbers represent averages over progressively longer periods of time (one, five, and fifteen-minute averages), and that lower numbers are better. Higher numbers represent a problem or an overloaded machine.
Read 22 tweets
23 Sep
Networking Basics!

How communication happens?
What are 7 OSI Layers?

#Linux #networking #basics #osi #DevOps

A thread πŸ‘‡
What Is the OSI Model?

The Open Systems Interconnection (OSI) model describes seven layers that computer systems use to communicate over a network. Image
Layer 1: Physical Layer

It represents the electrical and physical representation of the data connection / system.

When a networking problem occurs, many networking pros go right to the physical layer to check that all of the cables are properly connected. Image
Read 17 tweets
17 Sep
List of my Kubernetes Series (Part 1) Articles.

A Thread πŸ‘‡

#Kubernetes #cncf #DevOps #cloud #AUTOMATION #Linux
1. Kubernetes! πŸ€”

What's that!

blog.learncodeonline.in/kubernetes
2. Kubernetes Cluster Deployment on CentOS Linux!

blog.learncodeonline.in/kubernetes-clu…
Read 12 tweets
16 Sep
Collection of Cheat Sheets:

Linux Commands, Networking Tools, Hacking Tools, Docker, Kubernetes, AWS etc.

#Linux #infosec #DevOps #cheatsheet

A Thread. (Will continue to add more)
Linux Commands Cheat Sheet Image
Systemctl Commands Cheat Sheet Image
Read 22 tweets