Category Archives: What is?

Attempts to understand in some terms and concepts.

AWS: VPC Flow Logs, NAT Gateways, and Kubernetes Pods – a detailed overview

5 May 2024

 We have a relatively large spending on AWS NAT Gateway Processed Bytes, and it became interesting to know what exactly is processed through it. It would seem that everything is simple – just turn on VPC Flow Logs and see what’s what. But when it comes to AWS Elastic Kubernetes Service and NAT Gateways, things… Read More »

What is: SAML – an overview, its structure and requests tracing between a Jenkins and Okta SSO

17 November 2019

 During the SAML SSO configuration for our Jenkins, I faced an issue, when some attributes weren’t passed from Okta to the Jenkins instance. So in this post will try to figure out what is SAML in general, will take a short overview of its architecture and main components, and will make some SAML-requests tracing/sniffing to… Read More »

Kubernetes: part 1 – architecture and main components overview

25 July 2019

  On my current project for our mobile applications, we have an API-backend on the Yii PHP-framework, which is working now on an ordinary LEMP stack – Linux/NGINX/PHP-FPM/MySQL (AWS EC2 + MariaDB RDS). Eventually, it’s time to break this monolith into microservices which will be orchestrated by the Kubernetes and will be running on the… Read More »

Redis: replication, part 1 – an overview. Replication vs Sharding. Sentinel vs Cluster. Redis topology.

29 March 2019

 CodeProject Initially, it was planned to write one small post with an example how to create a Redis replication but as I read more and more details – I wanted to describe more and more about it, so eventually I split this post into two parts. In this one – some quick overview, a brief… Read More »

What is: chroot – system call and utility in Linux

23 March 2019

 chroot() was added to the Version 7 Unix in 1979 and used for filesystem isolation. In fact, it’s the predecessor of the whole current containerization idea, just now there are namespaces and cgroups are used while earlier chroot was used to create an environment which is isolated from a host and can be used for… Read More »

What is: YAML – its overview, basic data types, YAML vs JSON, and PyYAML

14 March 2019

 YAML – is one of the most popular formats of the… Well, actually, they don’t know the format of what… Originally it was the «Yet Another Markup Language», later it became «YAML Ain’t Markup Language»: Originally YAML was said to mean Yet Another Markup Language,[12] referencing its purpose as a markup languagewith the yet another construct, but it was then… Read More »