A little K8s knowledge every day! — To deal with object in K8s, you need to understand YAML well, whether creating/updating/deleting objects, you need to write some YAML files, and when you try to deploy your applications use HELM , you also need to write YAML file, to be honest, a K8s engineer is a “YAML” engineer…

A little Python knowledge everyday! — Without a doubt, functions are one of the most important concepts in Python. When doing coding, we break down big problems in the real world into small ones, and then process through functions. Functions are both the nemesis of repetitive code and the best weapon against code complexity. Most functions…

How to implement a Python type annotation checker — In my previous articles, I talked about Python variable type annotation, containers type annotation and function type annotation. I hope you’ve learned how to combine type annotations and mypy tools to perform static type checking for you code. However, mypy only does static type checking, during the program, there are…

Python type annotation deep dive — Annotate Parameters and Return Value To annotate the type for a function, you need to type annotate each formal parameter, and at the same time annotate the return value of the function. For example: def add(x: int, y: int) -> int: return x + y print(add(2, 5)) The variable type of the formal parameter is…

A little K8s knowledge every day! — kubectl kubectl is a command line tool (CLI) for K8s, an essential management tool for K8s users and administrators. kubectl provides a large number of subcommands to facilitate the management of various functions in a K8s cluster. Instead of listing the formats of various subcommands, Iwill introduce how to query the…

Advanced CIDR knowledge — Background and History If you are a DevOps engineer or SRE, you must have used one of these two commands: ifconfig and ip addr . For networking troubleshooting, usually you log into the host and check the network configuration and status by running: root@test:~# ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state…

A little K8s knowledge every day! — DNS is one of the core features of K8s, providing naming services through kube-dns or CoreDNS as a must-have extension for K8s cluster. Since K8s master stores all service definitions and updates, when client pod needs to communicate with backend pods which behind a load balancer, it needs to know…

Introduction to Terraform — Infrastructure as Code (IaC), is where the developer or DevOps engineer write code to achieve the end state of the infrastructure or server they desire. For example, to create an application load balancer, EC2 instance and a EBS volume in AWS. Terraform is an open-source infrastructure as code software tool…

Python type annotation deep dive — Continue the Python “Type Annotation” topic, in this article let’s talk about type annotation for container type like list, tuple, dict and set . Compare to normal variables, container type annotation is a little more troublesome. Annotating Set When using set, by default we only add values ​​of the same data type…