Istio Transition and Support Policy
This policy outlines the transition of UDS Core services from the traditional Istio sidecar model to Istio Ambient Mode.
Purpose of the transition:
- Lower resource requirements
- Simplified operations
- Improved latency
These benefits are particularly important as UDS expands its edge capabilities.
Applies to:
- All UDS Core services (e.g., logging, monitoring, SSO)
- All users deploying apps within UDS-managed environments
Does NOT apply to:
- Applications not managed by UDS Core
- Third-party infrastructure not provisioned through UDS tooling
Transition Details
Section titled “Transition Details”| Component | Transition Path |
|---|---|
| UDS Core Services | All deployments will use Istio Ambient Mode by default starting 0.43.0. |
| Mission Applications | Both sidecar and ambient modes supported. Ambient is opt-in and recommended. |
Support Policy
Section titled “Support Policy”| Deployment Type | Istio Ambient | Istio Sidecar |
|---|---|---|
| UDS Core Services | Fully supported | Not supported |
| Mission Applications | Supported & recommended | Supported |
| New Features | Prioritized for ambient | Evaluated case-by-case |
| Security & Patching | Provided | Provided (shared components) |
| Deprecation Plan | Active development | No planned deprecation |
Technical Guidance
Section titled “Technical Guidance”See this doc for additional Technical Guidance.
Frequently Asked Questions
Section titled “Frequently Asked Questions”Q: Do I need to switch my app to Ambient Mode? A: No. Sidecar mode is still supported, but Ambient is recommended.
Q: Will sidecar mode be deprecated for mission apps? A: No. It remains supported. Hybrid mesh (ambient + sidecar) is low-maintenance and will remain supported.
Q: What happens when I update UDS Core? A: UDS Core services will automatically use Ambient Mode. Mission apps are unaffected unless they explicitly opt in.
Q: Will Istio updates still apply to sidecar mode? A: Yes. Istio components are shared and continue to serve both Ambient and Sidecar modes with updates and patches.
Q: Does switching to ambient require replacing Istio? A: No. Ambient is an alternate data plane within Istio. The core control plane remains unchanged.
Q: How can I test or migrate to Ambient Mode? A: By upgrading to 0.43.0+ UDS Core services will automatically migrate to ambient mode. Mission apps can be switched to ambient by opting-in.