This document discusses moving legacy n-tier applications to container platforms like Docker and Kubernetes. It covers challenges like networking, discovery, load balancing, and persistence when containerizing applications. It then discusses how a DevOps approach can accelerate development and operations workflows through continuous delivery, integration, deployment, etc. The role of platforms like Kubernetes and Stratos in defining policies, composite applications, and auto-scaling container instances is also covered.

1. Last Updated: June. 2015
Bringing N-Tier Apps To Containers
Vice President, Platform Evangelism, WSO2
@cobiacomm
Chris Haddad

2. Moving from
Lab to Production

3. Moving from Old to New

4. Legacy 3-Tier Applications

5. Legacy Enterprise Topologies – Complex Interactions

6. N-Tier Perspectives
6
Solution Template
Infrastructure
Policy
Architecture

7. N-Tier Solution Attributes
o Architecture
o Application Oriented, Service-Oriented, Resource-Oriented
o Composition / Orchestration
o Policy
o Quality of Service
o Resiliency, High Availability, Scalability
o Security
o Isolation
o Infrastructure
o Topology
o Connectivity - Networking
o Resource Management - Scheduling, Reservation
o Storage
7

8. Architecture:
Application, Resource, Service-Oriented
8
Constraint Platform Requirement Kubernetes
Mesos
Marathon
Docker
Compose
Apache
Stratos
higher level, aggregate
view
application as first-class
citizen, labels N Y Y Y
Resource view
resource as first-class
citizen, labels, URLS Y N N N
Business capability view
service as first-class citizen,
labels Y Y N Y

9. Composition
9
Constraint Platform Requirement Kubernetes
Mesos
Marathon
Docker
Compose
Apache
Stratos
cluster (session and state
management)
network addressable,
coordination service N N N * N
container group (web app
database )
network overlays,
orchestration N N N Y
container links (web app ,
database )
network overlays,
orchestration
N (flat,
plug-in?) N ? Y Y
server farm register worker nodes Y Y N Y

10. Isolation
10
Constraint Kubernetes
Mesos
Marathon
Docker
Compose
Apache
Stratos
CPU, PID, Memory Y Y Y Y
Network N N (?) Y Y
Tenant Management N N N Y

11. Networking
11
Constraint Platform Requirement Kubernetes
Mesos
Marathon
Docker
Compose
Apache
Stratos
Load balancer (HW, SW)
known routes, hostname
addressing Y (plug-in) N ? Y
Public IP
public IP, hostname
assignment, route Y (plug-in) N Y Y

12. Resource Management
12
Constraint Platform Requirement Kubernetes
Mesos
Marathon
Docker
Compose
Apache
Stratos
CPU load
resource reservation,
scheduling * Y Y S
memory footprint
resource reservation,
scheduling * Y Y S

13. More Constraints
13
Category Constraint Platform Requirement
Security identity management
Security
network segment security
(web app, database) access control policies
Storage
shared access to database
service
Storage shared access to files shared volumes
Storage shared access to files networked drives
Topology Cross-Data Center cross-zone monitor and control
Topology Cross-IaaS cross-zone monitor and control
Topology pre-built, hardwired complex declarations

14. Moving N-Tier Apps to Containers

15. Containerization Adoption Barriers
Networking and
Load Balancing
Monitoring and QoS
Clustering
Backing Stores /
Persistence Strategies
Discovery and
Composition
Workflow

16. Common Level Zero
Container Challenges
o Networking
o Discovery
o Load balancing between Tiers
o Persistence – Tight Coupling with File System
o Monitoring and Log files
16

17. Operate at the Speed of BusinessAccelerate
DevOps Flow

18. Operate at the Speed of Business

19. o Deployment
o Discovery
o Linking
o Monitoring
o Resiliency

20. DevOps Vectors
o Continuous delivery
o Continuous build
o Continuous integration
o Continuous deployment

21. DevOps Vectors
o Reliability
o Availability
o Scalability
o Performance

22. o Iterative releases
o Incremental testing
o Co-evolution

23. Compass and Gearing
Platform Compass
Operations Perspective
• Manage Container Quality of Service
• Ensure Security
Development perspective
• Micro-service architecture patterns
• Application packaging strategies
• Container lifecycle decisions

24. Composite Application Model and Policy Model

25. *
What are the smart policies?
๏ Auto scaling
๏ Deployment
Auto scaling policy
๏ Define thresholds values pertaining scale up/down
decision
๏ Auto Scaler refer this policy
๏ Defined by DevOps
Deployment policy
๏ Defined how and where to spawn cartridge instances
๏ Defined min and max instances in a selected service
cluster
๏ Defined by DevOps based on deployment patterns
Smart Policies

26. *
Groups Compose Container Instances

27. *
Scaling algorithm can use multiple factors. such as
- Load average of the instance
- Memory consumption of the instance
- In-flight request count in LB
How do you specify elastic scale?

28. *
Group Scaling Scenario

29. *
Dependent Scaling Scenario

30. Internet as a Data Center
© Mathias Rosenthal - Fotolia.com

31. *
Burst based on policy and load
Ever try to Cloud Burst Containers?

32. *
Rapidly Evolve with Micro-service Applications

33. Infrastructure Alternatives
o Docker Compose
o Apache Mesos / Mesos Marathon
o Google Kubernetes
o Apache Stratos
33

34. *
Manage clusters and
containers
● Schedule
● Control
Concepts
● Pods
● Labels
● Nodes
Why add Kubernetes?

35. *
Kubernetes – Opportunity Zone
Source: https://github.com/GoogleCloudPlatform/kubernetes/blob/master/DESIGN.md
“we want Kubernetes to be built as a collection of pluggable
components and layers, with the ability to use alternative
schedulers, storage systems, and distribution mechanisms, and
we're evolving its current code in that direction.”
“A single Kubernetes cluster is not intended to span multiple
availability zones. Instead, we recommend building a higher-level
layer to replicate complete deployments of highly available
applications across multiple zones.”

36. *
The Role of Apache Stratos
● Package Manager
● Define Security and Network Policies
● Manage Micro-service Definition
● Define Composite Application
● Container Auto-Scaler Logic
● Manage Service Subscriptions

37. *
Containerize Applications and Services

38. *
Apache Stratos L1 Deployment Architecture
for Docker based Cartridges

39. Stratos Architecture

40. Test Drive the Cloud in a Box Distro
Install Kubernetes Distro:
https://github.com/imesh/kubernetes-vagrant-setup.git
Download Stratos distribution, load balancer & samples:
http://stratos.apache.org
Follow Getting Started Guide