Skip to content

Big Bang 3.0 - Operatorless Istio Migration📜

It has been nearly two years since the Big Bang 2.0 release, and the project has grown significantly in that time. The Big Bang engineering team is proud of the product that we have built alongside our growing community. Your support and feedback have been essential in shaping the platform your missions rely on.

In line with our mission-first principles, we want to share updates on the direction of Big Bang and what it means for you as Big Bang operators.

Istio operator deprecation📜

In August 2024, the Istio project announced the deprecation of the Istio Operator in Istio 1.24. The Istio Operator was created to address many of the problems with Helm 2. Helm 3 resolved many of those issues. Additionally, the Istio project’s data showed that less than 10% of installations used the operator, with most relying on istioctl for initial deployment and upgrades.

Big Bang prefers a declarative approach to package deployments. With Big Bang 3.0, we’ve extended that approach to installing Istio into Kubernetes clusters without the operator or istioctl. We’re doing this by leveraging the upstream base and istiod charts in accordance with Istio’s helm installation documentation.

Istio 1.23 has a generous EOL timeline, giving Big Bang engineers ample time to work through the migration. We’ve merged initial packages to enable operatorless Istio.

These packages are currently in an alpha state and subject to change. Big Bang consumers are advised to avoid running these packages in production environments. However, if users want to test the new packages with their custom configurations, they are available in Big Bang’s most recent release under istioCore, istioGatewayPublic, and istioGatewayPassthrough at the time of writing.

Because this new deployment paradigm is fundamentally incompatible with previous Istio deployments in Big Bang, this transition is marked as a breaking change. The Istio upstream project has set May 2025 as the EOL point for Istio 1.23 (including the Operator), so Big Bang is aiming for a 3.0 transition on or before that date.

Migration considerations📜

The Big Bang team is dedicated to making this transition as smooth as possible. We are actively working on migration documentation and automation where applicable.

Here are some key architectural changes you should be aware of:

Mesh operations📜

✅ No impact on existing mesh configurations

  • Your existing Istio CRs will continue to work as-is post-migration.
  • PeerAuthentication, ServiceEntry, and AuthorizationPolicy remain unchanged.
  • istiod continues to manage mesh operations—the operator removal does not affect this.

Gateways📜

🚨 Significant changes to Gateway deployments

  • Previously, Gateway configurations were embedded in IstioOperator CRs and managed by the operator.
  • In 3.0, Gateways must be installed via their own standalone Helm charts.
  • We are exposing the Istio gateway chart’s API directly to Big Bang consumers rather than continuing with an abstraction layer.

✅ Simplified Deployment with Iterable Helm Releases

  • We are developing an iterable istioGateway package to ease deployment.
  • Users can still deploy custom Gateway resources manually, but our new package will reduce friction.
  • More details on this feature will be shared in the coming weeks.

🔍 Exploring Kubernetes-native Gateway API

  • We are researching the K8s-native Gateway API as a potential primary ingress/egress configuration resource.
  • This transition would increase flexibility and potentially support alternative service mesh implementations in the future.

Ambient mode📜

We want to be clear that our transition to operatorless Istio is not a transition to Istio’s ambient mode.

We think ambient Istio is promising and are researching how best to support it. However, this migration only focuses on removing the Istio Operator. If and when we have a clear path for ambient mode, we’ll share updates.

Migration timeline📜

Currently planned milestones for Big Bang 3.0:

  • March 2025 – Operatorless Istio reaches beta status for broader testing.
  • April 2025 – Final testing phase for community feedback.
  • May 2025 – Big Bang 3.0 release, aligning with Istio 1.23 EOL.

What you need to do📜

✅ Test the new operatorless Istio packages in non-production environments.

✅ Review your Gateway configurations and prepare for standalone Helm-based deployment.

✅ Keep an eye out for migration documentation and automation tools.

✅ Engage with the community to provide feedback or raise concerns.

Community thanks📜

As always, we want to thank our community for their continued support. We build Big Bang for you, and our mission is to simplify and enable yours. If you have any feedback or concerns, please share them in our community Slack, on Mattermost, or by making an issue in repo1.