Compute Nest lets service providers publish new service versions and lets customers upgrade their existing service instances to those versions. Use this capability to ship bug fixes, add features, or update underlying cloud resources—without requiring customers to redeploy from scratch.
How it works
Compute Nest supports two update methods: updating by stack and updating by application. Update by stack is the recommended approach.
Update by stack
When a customer creates a service instance, Compute Nest provisions a resource stack based on the service template you defined in Resource Orchestration Service (ROS). When you publish a new service version, Compute Nest applies a least-invasive upgrade: it compares the ROS templates of the two versions and performs only the changes that differ, leaving unchanged resources untouched.
Given a service with versions V1 and V2:
| Resource state | What happens |
|---|---|
| Present in both versions, no property change | Remains unchanged (e.g., Resource A) |
| Present in both versions, property changed | Updated in place (e.g., Resource B) |
| Present in V1 only | Deleted (e.g., Resource C) |
| Present in V2 only | Created (e.g., Resource D) |
This approach upgrades cloud resources and software applications in a single operation.
Update by application
Application updates use CloudOps Orchestration Service (OOS) to run script commands on Elastic Compute Service (ECS) instances, replacing ECS images or software packages without modifying the stack. This method is suited for ECS-based deployments and is not supported for Container Service for Kubernetes (ACK)-based deployments.
To use this method, configure the OOS actions required to transition from the earlier version to the later version. OOS then executes those actions on the running service instance.
Application updates are invisible to the stack. If a stack update runs afterward, it may overwrite the application update. Use stack-based updates whenever possible.
Upgrade rules
The target version must be available to the service instance.
Upgrades can only move forward—from an earlier version to a later version.
Within the same account used to publish the service, a service provider can upgrade a test service instance to the draft version or beta version.
The draft version is the latest version and cannot be upgraded further.
The beta version is the second-latest version. It can be upgraded to the draft version. A published version can also be upgraded to the beta version.
Upgrade and rollback
Compute Nest treats rollback as the natural counterpart to upgrade. If an upgrade does not go as expected, roll back the service instance to restore it—no redeployment required.
Upgrade: Upgrade a single service instance from its service details page, or upgrade multiple instances at once from the O&M Management tab on the service details page. For step-by-step instructions, see Upgrade one or more service instances.
Rollback: Rollback reverses an upgrade, moving a service instance from a later version back to an earlier version. Customers can roll back to their previous version. To identify which version a service instance can be rolled back to, check the service update history.