06/28/2024:

Converted to sub-task for OSSM-6457 which is the Jira for the OSSM 2.6 Rel Notes so content and comments are preserved and more easily referenced for release note entries.

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Former Title: Determine if any upstream functionality is not supported in OSSM 2.6 release

This issue is for release notes related to upstream changes in Istio 1.19 or 1.20 that have not been captured in other issues. We should look to note:

• New features that we are not able to fully support that have not previously been noted.
• Notable new features or changes that are of known interest to customers
• Changes in behaviour that customers should be aware of
• Anything else important for users to know

Istio 1.19:

• Blog
• Upgrade notes
• Change Notes

Istio 1.20

• Blog
• Upgrade notes
• Change notes

Initial list:

[1.19]

[1.20]

• Envoy sidecars now configures a startup probe by default, meaning that the pod's readiness probes will not start until the Envoy sidecar has started. It's described in more detail in the 1.20 upgrade notes. This is a minor behavior change that may be worth noting.
• VirtualServices now support traffic mirroring to multiple destination hosts. This is described in the 1.20 blog, and change notes.