This page describes changes you need to be aware of when upgrading from Istio 1.2 to 1.3. Here, we detail cases where we intentionally broke backwards compatibility. We also mention cases where backwards compatibility was preserved but new behavior was introduced that would be surprising to someone familiar with the use and operation of Istio 1.2.
Installation and upgrade
We simplified the configuration model for Mixer and removed support for adapter-specific and template-specific Custom Resource Definitions (CRDs) entirely in 1.3. Please move to the new configuration model.
We removed the Mixer CRDs from the system to simplify the configuration model, improve Mixer’s performance in Kubernetes deployments, and improve reliability in various Kubernetes environments.
Istio now captures all ports by default. If you don’t specify container ports
to intentionally bypass Envoy, you must opt out of port capturing with the
Protocol sniffing is now enabled by default. Disable protocol sniffing with the
--set pilot.enableProtocolSniffing=false option when you upgrade to get the
previous behavior. To learn more see our protocol selection page.
To specify a hostname in multiple namespaces, you must select a single host using
Trust domain validation
Trust domain validation is new in Istio 1.3. If you only have one trust domain or you don’t enable mutual TLS through authentication policies, there is nothing you must do.
To opt-out the trust domain validation, include the following flag in your Helm
template before upgrading to Istio 1.3:
Secret discovery service
In Istio 1.3, we are taking advantage of improvements in Kubernetes to issue certificates for workload instances more securely.
Kubernetes 1.12 introduces
trustworthy JWTs to solve these issues.
introduced the ability to change the value of the
aud field to a value other
than the API server. The
aud field represents the audience in Kubernetes. To
better secure the mesh, Istio 1.3 only supports
trustworthy JWTs and requires
the audience, the value of the
aud field, to be
istio-ca when you enable
Before upgrading to Istio 1.3 with SDS enabled, see our blog post on trustworthy JWTs and SDS.