Kubernetes / K8s¶

Monolithic¶

Entire software run as single heavy process on expensive hardware
tightly couple
legacy design and architecture.
redundant logic, 1000 lines of code, no modern language and design principles.
built with a single technology stack
Not designed to take full advantage of cloud-native features such as cloud's elasticity/auto-scaling, managed services, and distributed architectures.
other challenges and limitation:
scaling of single feature in impossible, and scaling whole app is pricey.
upgrade : downtime and upgrade window.
failure in any part of a monolithic application can potentially bring down the entire system
Higher operational costs and less efficient use of computational resources.
size grows: new updates/features, keep on making appl more heavy.

architecture: https://chatgpt.com/c/2f54de12-b416-4a76-80a0-ebd286b0c467
small independent services, lightweight applications, for each business/feature.
On-demand scalability : run MS on different hosts /Availability
Optimal resource usage : run on matching hardware-requirement| efficeint | low cost.
distributed nature : whole app is distributed among many MS. which adds up some complexity.
Seamless updates(rollout)/rollbacks without any downtime.
Fault-tolerance:
system continues to operate properly in the event of the failure of some of its components
Service-discovery
process of automatically detecting network locations of service instances.
service registry - database of available service instances. eg : Netflix Eureka
- client --> service registry
- client --> load balancer > queries to service registry.

can run on Cloud and take full advantage of cloud.