Architecture decisions for networking

Network Architecture decisions

The following are networking architecture decisions for the Red Hat OpenShift on VPC pattern.

Architecture decisions for network
Architecture decision Requirement Alternative Decision Rationale
Connectivity for remote management of environments Provide secure and encrypted connectivity to the cloud’s private network for management purposes.
  • Client VPN for VPC
  • VPN for VPC
Client VPN for VPC Client VPN for VPC provides client-to-site connectivity, which allows remote devices to securely connect to the VPC network that uses an OpenVPN software client.
Network Segmentation and Isolation: Web App
  • Deploy the workloads in an isolated environment and enforce information flow policies.
  • Provide isolated security zones between app tiers
  • Virtual Private Clouds (VPCs)
  • Subnets
  • Security Groups (SGs)
  • ACLs
VPCs, subnets, Security Groups (SGs) and ACLs VPCs provide secure, virtual networks for web apps, which are logically isolated from other public cloud tenants. Subnets provide a range of private IP addresses for each web app tier within a zone. Security Groups and ACLs are used as firewalls to limit access to virtual servers and web app tiers.
Connectivity to Cloud Services Provide secure connection to Cloud Services
  • VPC Gateway and Virtual Private Endpoints (VPE)
  • Private Cloud Service endpoints
  • Public Cloud Service Endpoints
Virtual Private Endpoints (VPE) VPC Gateway and Virtual Private Endpoints enable connectivity to IBM Cloud services by using private IP addresses allocated from a VPC subnet.
VPC to VPC Connectivity Connect two or more VPCs over a private network
  • Local Transit Gateway
  • Global Transit Gateway
Local Transit Gateway (TGW) The Local Transit Gateway enables connectivity between the Management and Workload VPCs.
Application Load Balancer Route web user http/https requests
  • VPC ALB
  • VPC NLB
  • HA proxy on VSI
VPC ALB

VPC ALB is recommended for web-based workloads.

  • Provides layer 4 and layer 7 load-balancing
  • Supports HTTP, HTTPS, and TCP requests
  • Supports SSL offloading.
Public DNS Provide DNS resolution to support the use of hostnames instead of IP addresses for applications
  • IBM Cloud Internet Services (CIS)
  • IBM Cloud DNS
IBM Cloud Internet Services (CIS) IBM Cloud Internet Services support provisioning and configuring DNS records for public DNS resolution and can be integrated with the public VPC ALBs for the web tier.
Global Load balancer Load balancing static content at IBM POP/CDN locations
  • IBM Cloud Internet Services (CIS)
  • F5
IBM Cloud Internet Services (CIS) IBM Cloud Internet Services support global load balancing and can act as perimeter security for the internet facing workloads.
Exposing services, Routing & Load Balancing in Red Hat Openshift Load balancing and routing across multiple instances of services in Red Hat Openshift
  • Routes in Red Hat OpenShift
  • Nginx ingress gateway
  • External Load balancer
Routes in Red Hat OpenShift Routes are integrated into the Red Hat OpenShift platform and are managed through Red Hat OpenShift API. It provides both hostname-name and path-based routing. They work seamlessly with other Red Hat OpenShift components.
Separation of concern traffic management and distribution across microservices Fine grained control over traffic distribution and intelligent load balancing for application microservices
  • Routes in Red Hat OpenShift
  • Red Hat OpenShift Service Mesh
Red Hat OpenShift Service Mesh Red Hat OpenShift Service Mesh provides advanced traffic management, service mesh features, security, and layer 7 load balancing.
Segment and control communication between the pods within the Red Hat Openshift cluster Define communication rules between pods for a more secure and controlled environment
  • Red Hat OpenShift SDN
  • Custom CNI
Red Hat OpenShift SDN Red Hat OpenShift Software-defined Networking (SDN) is the underlying network infrastructure that facilitates the implementation of Network policies. Network policies use the Red Hat OpenShift SDN to enforce rules.
Environment isolation Isolate production and nonproduction environments
  • Single VPC multi subnets
  • Separate VPC
Separate VPC for production and nonproduction Different environments are hosted in different Virtual Private Cloud (VPC). The production environment is deployed separately in a VPC from environments with fine-grained Network Access Control Lists (NACLs).