This epic is to cover work needed to provide support for Istio's multi-cluster topologies, namely (in priority order):

1. Multi-primary
2. Primary-remote
3. External control planes

This should include validation and documentation with the sail-operator on OpenShift, leading to product documentation on how to configure these topologies with the OSSM 3 product operator on OpenShift. If there are feature gaps in the sail-operator that prevent these topologies from being deployed, those should be addressed.

Notes:

• This work is independent of federation with OSSM 3, which is covered by: https://issues.redhat.com/browse/OSSM-4028
• This epic does not include efforts to automate configuration and management across multiple clusters (as could be achieved by something like ACM) - we will consider such things post 3.0 GA. The scope should be limited to what can be achieved with the Sail-operator alone, meaning that each cluster will require its own operator installation and configuration.

Related 2.x Dev Preview epic: https://issues.redhat.com/browse/OSSM-5435