Introduction to Kubernetes | Basics of YAML, Linux, Docker

YAML (Write a separate short blog on this)

And as learning from prerit munjal explain little bit about yaml here and redirect to you detailed blog

Data Serialization:

The data is stored in structures like trees, arrays, graphs, etc.

• When transferring data from 1 place to another we can’t directly send it in the form of data structures.

NOTE: Camel Casing:

• surajBro ( In Kubernetes manifest file we use camel casing)

Linux

Commands used:

ls
ls -a
ls -ll or ls -ltr or ls -la or ls -lh
touch suraj.txt
nano
vim 
ps 
ps aux
pstree
ps -t -u syslog
# This is to encode
echo Suraj | base64
# This is for decode
echo "encode value" | base64 --decode
# display the first 10 lines of a file
head suraj.txt # used when we have to see configurations files
# Display the last 10 lines of a file
tail suraj.txt # used when we have see logs

# Networking commands
tcpdump

# If we want to see just 10 packets
tcpdump -c 10

#
tcpdump -c 2 -w suraj.txt # This will return something "enp1s0"

# 
tcpdump -i enp1s0 -c 2 -w suraj.txt

# stream operator

tcpdump -i enp1s0 -c 2 > suraj.txt
tcpdump -i enp1s0 -c 2 >> suraj.txt

## important commands
# used when you want to communicate directly with containers
crictl 

crictl pods

crictl ps -a 

crictl logs "container id paste here"

# ctr is specifically used for containerd
ctr

# 
journalctl

## read about systemd
cd /etc/systemd
# in this location there is file called journald.conf which journal daemon which means keep running

#
journalctl --no-pager

#
journalctl --since yesterday

# -o means output
journalctl --since yesterday -o json-pretty

Kubernetes:

borg and omega

Kubernetes was open source in 2014 and Google gave this to CNCF Kubernetes is CNCF’s first hosted project.