Containerization architecture
Containerization is a deployment approach that packages an application along with its run-time dependencies, libraries, and configuration into a standardized, portable unit called a container. Containers ensure that applications run consistently across different environments, from development through production.
In the context of Pega Infinity™, containerization represents a strategic shift from traditional, virtual machine-based deployments to cloud-native, container-based deployments using Docker and Kubernetes. Pega positions containerization as the standard deployment model for both private and public cloud environments.
From a Lead System Architect (LSA) perspective, containerization is not about implementing a specific infrastructure, but about architecting scalable, resilient, and operationally sound Pega solutions that are aligned with modern enterprise and cloud standards.
Containerization in Pega
In a Pega-based environment, containerization refers to packaging and running Pega Platform™ and its supporting services as Docker containers, orchestrated by Kubernetes across cloud or on-premises environments. This standardized approach enables:
- Predictable and repeatable deployments
- Automation through CI/CD pipelines
- Easier adaptation across infrastructure choices
- Extension with client-specific configurations
Containerization enables Pega applications to align with cloud-native architectures while improving reliability, scalability, and operational efficiency in enterprise environments.
Pega Platform architectural evolution: from VM-based to containerized deployments
The following diagram sets the context for Pega Platform’s architectural modernization journey, illustrating the transition from a traditional, virtual machine-based deployment model to a cloud-native, containerized architecture using Docker and Kubernetes.
The diagram contrasts the legacy 'before' state, which is marked by tightly coupled infrastructure and complex update processes, with the modern 'after' state, where containerization simplifies deployments, reduces operational complexity, and enables greater agility, scalability, resilience, security, and alignment with contemporary microservice-driven software practices.
Docker and Kubernetes play a central role in Pega Platform’s transition to a modern, cloud-native deployment model. Docker provides an open platform for packaging Pega Platform and its dependencies, such as libraries and runtime components, into lightweight, portable containers. By standardizing how applications are built and run across environments, Docker enables faster development, testing, and deployment cycles while reducing inconsistencies between infrastructure setups. This containerized approach replaces the tightly coupled, VM-based deployments shown in the ‘before’ state, significantly simplifying application updates and reducing operational overhead.
Kubernetes complements Docker by orchestrating and managing these containers at scale. As an industry standard, open-source platform for container orchestration, Kubernetes automates the deployment, scaling, and operation of containerized workloads, ensuring high availability and resilience. In the ‘after’ state depicted in the diagram above, Kubernetes manages multiple Pega Platform pods, distributes workloads efficiently, and supports declarative configuration and automation.
For more information, see Understanding the Pega Platform deployment architecture
Core architecture components
The following list describes the core architectural components of a modern Pega Platform deployment in a containerized, cloud-native environment. The list explains how the Pega Platform is structured as a distributed system of collaborating nodes, how it is packaged as immutable Docker images, and how Kubernetes orchestrates run-time operations, scaling, and availability.
In addition, the list highlights the role of supporting services, externalized dependencies, and access mechanisms that enable Pega Platform to operate as a resilient, scalable, and cloud-native enterprise platform.
1. Distributed System Architecture
Pega Platform is deployed as a distributed system, consisting of one or more tiers of Pega nodes forming a cluster. These nodes collaborate to run application logic and interact with a relational database for Rules and data access.
2. Docker Images
Pega provides specific Docker images for deploying Pega Platform. Clients obtain licenses to download these images and push them to their own container registries. These images serve as immutable deployment artifacts across environments.
3. Kubernetes Orchestration
Kubernetes manages containerized Pega deployments by automating deployment, scaling, availability, and lifecycle management. A typical architecture includes:
- Pega Pods – Run-time containers that run Pega node roles
- Constellation Service – A microservice that delivers static UI assets such as JavaScript, CSS, HTML, and images
- Stream Service – A multi-tenant messaging service abstracting the Kafka API
- Search Service – A dedicated service supporting search and reporting features
4. External Services
To support cloud native scalability and performance, Pega connects to externalized services such as:
- Elasticsearch – Required for search and reporting
- Kafka – Used by the Stream Service
- Cassandra – Optional datastore for specific data scenarios
5. Access Management
User and system access to Pega Platform is managed through load balancers or Kubernetes ingress, which route traffic to exposed Pega nodes.
Containerized deployment with Pega software
In a containerized deployment, different responsibilities are isolated into separate containers. For example:
- One container runs the database server along with its required components.
- Another container runs the application server (such as Tomcat), and includes the necessary database drivers for connectivity.
This separation improves scalability, fault isolation, and operational management. Containers can be independently scaled, restarted, or replaced without impacting the entire system, which aligns with enterprise high-availability requirements.
As containerized systems grow in complexity, orchestration becomes essential. Kubernetes provides this orchestration layer for Pega deployments by automating:
- Pod deployment and lifecycle management
- Horizontal scaling
- Load balancing
- Configuration and secrets management
In Kubernetes, Pega applications run inside pods, which are the smallest run-time units. Configuration updates are externalized using Kubernetes constructs such as ConfigMaps, allowing changes to be managed independently of container images.
For more information, see Containerized deployments in Kubernetes environments
Key architectural shift
Modern enterprise platforms are undergoing a fundamental architectural shift as organizations move from infrastructure-centric designs to cloud-native architectures. This shift is driven by the need for greater scalability, resilience, faster change, and operational efficiency - demands that traditional, static infrastructure was not designed to handle.
As applications grow in scale and complexity, architectures must evolve to decouple responsibilities, externalize shared services, automate scaling, and adopt consistent, repeatable deployment models.
For Pega, this evolution is realized through the transition from VM-based architectures to containerized, Kubernetes-orchestrated platforms. Understanding why this architectural shift is happening is essential for Lead System Architects, as it directly shapes how Pega applications are designed, deployed, scaled, and operated.
The table below summarizes the key architectural shifts that LSAs must understand in this transition:
| Traditional model | Containerized model |
|---|---|
| Monolithic VM | Microservice oriented architecture |
| Embedded services | Externalized services |
| Manual scaling | Kubernetes driven scaling |
| Environment-specific deployments | Immutable, image-based deployments |
Check your knowledge with the following interaction:
This Topic is available in the following Module:
If you are having problems with your training, please review the Pega Academy Support FAQs.
Want to help us improve this content?