Hello Rakesh,
Welcome to the Microsoft Q&A platform!
Yes, you can technically create a duplicate network segment with the same IP range within your AVS environment without connecting it to a Tier-1 gateway. This setup is known as a disconnected or isolated segment. It allows you to access the segment within AVS via its vCenter without routing traffic outside the AVS environment. However, this approach is not recommended for anything beyond very short-lived, isolated testing.
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