What are the advantages of sharing Azure Subscriptions?

Question

We are currently running two parallel projects that appear similar from a bird's-eye view but differ significantly when you zoom in.

Project #1 runs on: AKS, vanilla OpenAPI Gateway (with Ingress Istio Gateway), self-managed Jenkins, Azure Monitor, and Azure Event Hub.

Project #2 operates on self-managed K8s, its own API Gateway, JaaS, Dynatrace, and Kafka.

Both projects have reached a level of maturity where re-architecting them is not a practical option. We are now exploring opportunities to create synergies between the two projects. Some questions we need to address are:

Should we merge the two projects within the same data centers?

If we choose to merge, should they run on the same Azure subscription or different subscriptions?

If they share the same subscription, what benefits would this provide? Are there common services that we are not aware of where co-locating the projects would reduce complexity and costs?

If they run on different subscriptions, are there any recommendations for sharing, such as a "management subscription" (referring to the Data Landing Zone & Data Management Landing Zone concept: https://learn.microsoft.com/en-us/azure/cloud-adoption-framework/scenarios/cloud-scale-analytics/architectures/data-management-landing-zone

I appreciate your input and insights.

Answer 1

Hi @Xcessiv ,

Sharing Azure subscriptions can have several advantages, including easier manageability, simpler networking, and easier team collaboration. By having both projects on the same subscription, it would be easier to manage all resources in a single pool, and it would be simpler to make updates across all resources.

Additionally, networking effort would be simpler since all resources would be in the same subscription. Team collaboration would also be easier since everyone would be working in the same subscription, making it easier to share resources and reassign VMs to coworkers.

However, it is important to keep in mind that subscriptions serve as a scale unit for component workloads to scale within platform subscription limits, so it is important to consider the scale of the projects before deciding to share a subscription.

Pros and cons of the changes that you have put forward would depend on various attributes related to reliability, architecture, etc. which differs from environment to environment so I would recommend going through the related documents mentioned below in the references section. As you were already following Cloud Adoption Framework documentation, to learn more about recommendations for sharing, go through this document which might be helpful. Also, this discussion page might be helpful for architecture related questions.

References:

• Subscription considerations and recommendations
• Subscription Topology
• Azure Architecture Center
• Azure Reliability
• Cloud Adoption Framework for Azure