What does API gateway do?🕵🏼

👣 (1) The client sends an HTTP request to the API gateway.
👣 (2) The API gateway parses and validates the attributes in the HTTP request.
👣 (3) The API gateway performs allow-list/deny-list checks.
👣 (4) The API gateway talks to an identity provider for authentication and authorization.
👣 (5) The rate limiting rules are applied to the request. If it is over the limit, the request is rejected.
👣 (6,7) Now that the request has passed basic checks, the API gateway finds the relevant service to route to by path matching.
👣 (8) The API gateway transforms the request into the appropriate protocol and sends it to backend microservices.
👣 (9-12) The API gateway can handle errors properly, and deals with faults if the error takes a longer time to recover (circuit break). It can also leverage ELK (Elastic-Logstash-Kibana) stack for logging and monitoring. We sometimes cache data in the API gateway.

#api #app #architecture
#SystemDesign #HTTP

How its Linux Boot Process works ? 🕵🏻‍♂️

🔌 When we turn on the power, BIOS or UEFI firmware is loaded from non-volatile memory, and executes POST (Power On Self Test).
💽 BIOS/UEFI detects the devices connected to the system, including CPU, RAM, and storage.
💿 Choose a booting device to boot the OS from. This can be the hard drive, the network server, or CD ROM.
📀 BIOS/UEFI runs the boot loader (GRUB), which provides a menu to choose the OS or the kernel functions.
🖥 After the kernel is ready, we now switch to the user space. The kernel starts up systemd as the first user-space process, which manages the processes and services, probes all remaining hardware, mounts filesystems, and runs a desktop environment.
📟 systemd activates the default. target unit by default when the system boots. Other analysis units are executed as well.
🎚The system runs a set of startup scripts and configure the environment.
📱The users are presented with a login window. The system is now ready.

#linux #boot #systemdesign

Unleashing the Power of Cluster API: Extensibility and Customization - Zain Malik & Nibir Bora

#presentation #kubecon2024 #china #kubernetes

https://www.youtube.com/watch?v=nIWy1Hzl_oQ

Kubernetes as a Platform Framework: Journey from IaC Pipelines to K8s APIs - Christina Andonov, AWS

#presentation #kubernetes #gitops

https://www.youtube.com/watch?v=TBzy0QPOyY4

There are more than 500+ Kubernetes Certified Service Providers and tons of Kubernetes Certified distributions. Choosing a right distribution can be a daunting task. Kubetools is built with a purpose to build a curated list of popular Kubernetes tools🙈

#kubernetes #devops #infrastructure

https://collabnix.github.io/kubetools

😇In my opinion, KCL is a very promising thing for reliable and fast writing of configuration for any purpose, be it the cloud or just for applications

KCL: Simplifying Kubernetes Manifests Management

#devops #configuration #infrastructure

https://www.kcl-lang.io/blog/2024-08-29-kubecon2024

🌱 Typical AWS Network Architecture in one diagram.

🟣Internet Gateway (IGW) serves as the doorway between your AWS VPC and the internet.
🟣Remote Workers AWS offers a Client VPN service that enables remote workers to access securely over the internet.
🟣VGW is the VPN concentrator on the Amazon side of the Site-to-Site VPN connection between your network and your VPC.
🟣VPC Peering allows you to connect two VPCs.
🟣AWS Transit Gateway acts as a network transit hub, enabling you to connect multiple VPCs, VPNs, and AWS accounts together.
🟣VPC Endpoint (Gateway type) allows you to privately connect your VPC to supported AWS services and VPC endpoint services powered by PrivateLink without requiring an internet gateway, VPN.
🟣Interface VPC Endpoint enables private connections between your VPC and supported AWS services.
🟣SaaS AWS Private Link Connection provides private connectivity between VPCs and services hosted on AWS or on-premises.
#aws #infrastructure #network

What does ACID mean? For SQL 🗄
🔹 Atomicity
The writes in a transaction are executed all at once and cannot be broken into smaller parts. If there are faults when executing the transaction, the writes in the transaction are rolled back.
🔹 Consistency
Unlike “consistency” in CAP theorem, which means every read receives the most recent write or an error, here consistency means preserving database invariants. Any data written by a transaction must be valid according to all defined rules and maintain the database in a good state.
🔹 Isolation
When there are concurrent writes from two different transactions, the two transactions are isolated from each other. The most strict isolation is “serializability”, where each transaction acts like it is the only transaction running in the database. However, this is hard to implement in reality, so we often adopt loser isolation level.
🔹 Durability
Data is persisted after a transaction is committed even in a system failure.

#databases #infrastructure #devops #SQL

What happens when a junior DevOps specialist is forced into the main branch of the production infrastructure ? 🤪

#humor #git #devops

🍉 I bring to your attention some very interesting thoughts from the mini-guide from the Port https://www.getport.io/ , in which you will find out.
👉🏼 The next big thing in DevOps is platform engineering, and the main tool it uses is the internal developer portal. Read this guide to understand what can be done with portals and why they matter.

#books #guide #devops #platformengineering

💾A Linux file system is the method and data structure that Linux uses to control how data is stored and retrieved on a disk. Without a file system, data placed in a storage device would be a large body of data with no way to tell where one piece of data ends and the next begins. The file system is what allows Linux to organize data into files and directories, making it easier to access and manage
📲 Main Directory's Structure:
/root directory (/) is the topmost directory in the Linux file system hierarchy. It serves as the starting point from which all other files and directories branch out. Every file and directory on a Linux system can be accessed by following a path from /
/bin Essential user binaries
/etc Configuration files
/home User home directories
/var Variable files
/tmp Temporary files.

Linux's flexible file system design allows for multiple types of file systems to coexist and be used according to the needs of the system or storage.

#infrastructure #linux #devops

🫠 Very useful tips that you need to follow when developing an application that works with AWS S3, in order to avoid large expenses in the future.

#aws #devops #infrastructure #application

https://medium.com/@paulgoll/how-to-lose-money-with-aws-s3-a-cautionary-tale-c48549bee6ac

👔 This post contains up-to-date information on sites for finding a it (devops) remotely job in companies and startups.

1️⃣ Of course, https://www.linkedin.com/. This social network is one of the most important broadcasters of vacancies in the IT sphere. In order to receive more offers, it would be nice to pump up your profile.
2️⃣ https://angel.co/jobs - Platform for finding jobs in startups.
3️⃣ https://weworkremotely.com/ - The largest remote work community in the world. With over 4.5 million visitors, WWR is the number one place to find work.
4️⃣ https://indeed.com - Will help you find remote work all over the world.
5️⃣ https://www.fiverr.com/ - Work for IT specialists, mostly freelance.
6️⃣ https://remotive.com/ - Large community to help remote workers.
7️⃣ https://remoteok.com/ - Not a bad job search engine. No need to create an account, you will simply be asked to send your resume or portfolio to email addresses after you fill out the form.
8️⃣ https://www.idealist.org/ - A good platform with a large number of different internships, including remote ones.
9️⃣ https://dribbble.com/ - Site mainly for designers, lots of remote vacancies.
🔟 https://www.glassdoor.com/ - The site offers the ability to search for vacancies in most countries.
1️⃣1️⃣ https://www.jobisjob.com/ - I would especially like to highlight this - an excellent resource that collects offers from all sites practically from all over the world.
1️⃣2️⃣ https://www.monster.com/ - Large international portal. First, it offers to decide on the geography of future work, and then look at the results.
1️⃣3️⃣ https://www.dice.com/ - Similar to the previous one, it is considered one of the best resources for finding technical and engineering jobs.
1️⃣4️⃣ https://www.careerbuilder.com/regional_sites - An interesting portal for finding work in the USA.

I hope this post will be useful to start your career! 🤗

#kubernetes #humor #devops

🗃 What is Docker?

Docker allows you to package an application with all its dependencies into a standardized unit for software development and deployment.

Key Concepts:

📪 Containers
- Lightweight, standalone executable packages
- Include everything needed to run an application
- Ensure consistency across different environments

📫 Images
- Read-only templates used to create containers
- Built from layers, each representing an instruction in the Dockerfile
- Can be shared via Docker Hub or private registries

📭 Dockerfile
- Text file containing instructions to build a Docker image
- Defines the environment inside the container
- Automates the image creation process

🚀Getting Started:
1. Install Docker
2. Familiarize yourself with basic commands (docker run, build, pull, push)
3. Create your first Dockerfile and build an image
4. Experiment with Docker Compose for multi-container setups
5. Explore Docker Hub for pre-built images and inspiration

#humor #application

🤓 The choice of an API architecture can have significant implications on the efficiency, flexibility, and robustness of an application.

Let’s examine some prominent styles:
𝗥𝗘𝗦𝗧
A cornerstone in web services, REST leverages HTTP methods for streamlined operations and a consistent interface.
𝗚𝗿𝗮𝗽𝗵𝗤𝗟
Whilst REST uses multiple endpoints for each resource and necessitates multiple requests to obtain interconnected data
𝗦𝗢𝗔𝗣
Once dominant, SOAP remains vital in enterprises for its security and transactional robustness.
𝗴𝗥𝗣𝗖
gRPC is efficient in distributed systems, offering bidirectional streaming and multiplexing.
𝗪𝗲𝗯𝗦𝗼𝗰𝗸𝗲𝘁𝘀
For applications demanding real-time communication, WebSockets provide a full-duplex communication channel over a single, long-lived connection.
It's popular for applications requiring low latency and continuous data exchange.
𝗠𝗤𝗧𝗧
MQTT is a lightweight messaging protocol optimized for high-latency or unreliable networks.