Exam 1z0-997-22 topic 1 question 22 discussion

A company runs a public-facing application that uses a Java-based web service via a RESTful API in their on-premises data center. Use of the API is expected to double with a new product launch. The business wants to migrate their application to Oracle Cloud Infrastructure (OCI) to meet the scale and reliability requirements.
In order to achieve this, they will divert only 40% of the traffic to the new Apache Tomcat web servers running on OCI and serve the remaining 60% traffic through their on-premises infrastructure. Once the migration is complete and application works fine, they will divert all traffic to OCI.
How can these requirements be met with the LEAST amount of effort?