Control plane vs data plane in BYOC: What runs where?

Control plane vs data plane in Bring Your Own Cloud (BYOC) is a separation of responsibilities: the control plane manages deployments and configuration, while the data plane runs applications and processes workload data. In a common BYOC architecture, the vendor hosts the control plane and your cloud account hosts the data plane. Some deployments place both planes in your environment.

For your enterprise, evaluating BYOC means understanding both where components run and who operates them. This guide explains that boundary, which data can leave your account, and what to check about access, upgrades, and control-plane outages.

In a common BYOC architecture, the vendor hosts the application platform's control plane, while the data plane runs in your cloud account.

• The control plane manages resources. It handles deployment configuration and management operations. The data plane executes application code and processes workload data.
• Location and management are separate. Your enterprise can own the cloud account while the vendor operates the platform and manages the workload infrastructure.
• Data placement needs a category-by-category check. Workload data, metadata, logs, build artifacts, secrets, and backups may have different storage and access arrangements.
• Check dependencies before assuming independence. Confirm what continues during a management outage and whether your requirements also call for a control plane inside your environment.

The control plane configures and manages the system; the data plane performs the work the application exists to do.

For an application platform, changing a deployment's configuration is a control-plane operation. An application receiving a request, querying a database, and returning a response performs data-plane work.

The following comparison describes a common BYOC split. Individual products can place components differently.

Both planes contribute to the same service. Compare their roles and dependencies rather than choosing between them.

In a common BYOC deployment, the data plane runs in your cloud account and VPC, while the application platform control plane runs in the vendor’s environment. A forward-deployed arrangement can place the platform control plane in your environment as well.

Your environment may contain worker nodes, application containers, databases, persistent volumes, and ingress components. It can also contain vendor-installed agents, controllers, and monitoring components. A hosted control plane therefore does not mean every piece of management software runs outside your account.

The management path connects your deployment tools to the platform and its cluster integration. The application path connects your users or internal services to the running workload and its data stores. Keeping these paths separate helps your team identify which connections are required to deploy software and which are required to serve requests.

The Kubernetes control plane and the application platform control plane are different layers. Kubernetes manages cluster state and schedules workloads; the platform control plane manages the developer-facing deployment workflow across its connected infrastructure.

Kubernetes includes an API server, scheduler, controllers, and a state store. Worker nodes run the containers. These are separate components, even when a platform presents them through one interface.

With managed Kubernetes, the cloud provider may operate the cluster control plane. For your deployment, identify who operates each control plane and who manages cluster upgrades.

A BYOC control plane communicates with the workload environment through a management integration, such as a cluster API or a local agent. That connection carries deployment instructions and operational status. Application requests can follow a separate path directly to the data plane.

Consider an internal API connected to a private database in your cloud. A simplified release follows this sequence:

1. A developer or CI workflow requests a new application version through the platform's management interface.
2. The platform checks the request's permissions and applies the deployment configuration through its cluster integration.
3. The cluster starts the application containers using the selected image and runtime configuration.
4. Application clients reach the API through its configured endpoint; the API queries the database and returns responses.

The management request and the application request follow different paths. The platform can manage an API without relaying every request to that API through its central management service.

For your application, trace ingress, authentication, storage, and outbound calls separately. Those paths determine which services must be reachable for a request to succeed.

BYOC does not automatically keep every data category in your cloud account. Workload data can remain local while control-plane metadata, logs, metrics, build images, or backups are stored elsewhere. Check each category’s destination and configuration separately.

Start with the application payload, then inspect the information generated while building, deploying, monitoring, and supporting it. A request body written into an error log remains sensitive even if the logging system classifies it as telemetry. Likewise, a resource name or configuration value should be assessed by its contents, rather than assumed harmless because it is metadata.

With standard Northflank BYOC, workloads run in your cloud account and Northflank hosts the platform control plane. Other data storage locations depend on the category and configuration:

If your build process must stay within an approved environment, Northflank lets you select build infrastructure: the deployment cluster, a separate build cluster, or Northflank's build infrastructure. Build execution and image storage are separate choices.

If your project’s build images must remain in your cloud account, Northflank supports a custom build registry. Select it when creating the project; that selection cannot be changed on an existing project. For backup residency, configure an appropriate global backup destination.

Map secrets separately: where they are stored, who can retrieve them, how workloads receive them, and whether support or deployment credentials provide another access path. Encryption, storage location, and administrative authority answer different questions.

In a typical managed BYOC arrangement, the vendor operates the hosted platform control plane, your enterprise owns the cloud account, and your team owns the application. Kubernetes lifecycle, infrastructure maintenance, and recovery responsibilities depend on the product and service agreement.

For each layer, identify an operator and an escalation owner. Your cloud team may govern the account, permissions, network boundaries, and billing. The platform vendor may provision clusters and maintain platform components. Your application team still needs ownership of application behavior, release decisions, and data-recovery requirements.

Write down who responds when a node fails, a database needs restoring, an upgrade affects an application, or a management credential is revoked. “Vendor-managed” is too broad to assign every incident automatically.

If your team already operates Kubernetes, Northflank provides Bring Your Own Kubernetes (BYOK). Your team retains cluster provisioning, version upgrades, node management, and underlying networking and storage components; Northflank manages its installed platform components and workload orchestration. Imported clusters must meet the requirements, and Northflank recommends a new, dedicated cluster for import.

Northflank provisions and manages the cluster with BYOC. If your team is still deciding how much operational responsibility to take on, compare BYOC, self-hosting, and managed cloud.

The BYOC data plane can continue serving existing workloads during a control-plane outage only if the required runtime dependencies remain available. Deployments, scaling, credential renewal, or recovery may still be affected. The behavior depends on the architecture and must be tested.

Running workloads in your own account does not prove that they can operate without the vendor’s management services. Ask which operations require an active management connection and test the consequences of losing it.

Evaluate at least four scenarios:

• Serving traffic: Can existing application instances accept requests without a management API call?
• Changing deployments: Can you release, roll back, or change configuration during the outage?
• Replacing capacity: Can the system replace failed instances or add nodes, and which control plane does that require?
• Renewing dependencies: What happens when credentials expire, an image must be pulled, or a restore is needed?

An application can continue serving at its current capacity and still lose its ability to recover from a second failure. Test the specific management disconnection you expect, then record which operations continue, which stop, and how service is restored.

A forward-deployed control plane runs inside your environment. It becomes relevant when your enterprise prohibits externally hosted management, requires management data to remain inside its boundary, or needs disconnected operation.

Moving application compute into your VPC addresses only part of that requirement. Review management connectivity, identity dependencies, update delivery, observability, and support access before deciding whether a deployment can operate within the required boundary.

Agree who operates, upgrades, backs up, and recovers the local management services. Placement alone does not make the platform self-hosted. If local management is a requirement, compare platforms that support forward-deployed control planes.

In standard Northflank BYOC, Northflank hosts the platform control plane while workloads run in your own cloud account. Northflank provisions and manages the Kubernetes cluster, including upgrades, scaling, and maintenance. Enterprise forward deployment can also place the platform control plane in your environment.

For self-serve BYOC, connect your cloud account and configure the cluster where workloads will run. Your cloud provider bills the infrastructure separately from Northflank's platform charges.

Start with the BYOC and BYOK requirements, then select the deployment boundary that matches your team: a Northflank-managed BYOC cluster, an eligible cluster your team operates, or an Enterprise forward-deployed control plane. Decide data-location settings before creating projects and approving the architecture.

These distinctions help when reviewing a vendor's architecture.

The data plane includes application execution, traffic processing, and relevant storage. It is broader than a database: APIs, background workers, and inference services also perform data-plane work.

A hosted control plane does not necessarily receive application traffic. Requests can go directly to the workload environment, depending on the architecture. Inspect gateways, proxies, and authentication dependencies to establish the actual path.

BYOC and self-hosting assign operational responsibility differently. BYOC can combine your infrastructure ownership with vendor-managed operations; self-hosting makes your team responsible for operating the software. Physical location alone does not determine the model.

A local data plane does not remove every vendor dependency. Management, releases, credentials, support, or recovery may still depend on the vendor. Evaluate continued operation and your ability to migrate separately.

Continue with the deployment and management decisions behind the architecture:

• BYOC vs self-hosting vs managed cloud
• Which platforms support forward-deployed control planes?
• Is BYOC the future of software deployment?
• How to manage workloads across cloud, customer VPCs, and on-premises environments