Hello
Thank you for your question and reaching out. I can understand you are having query related to Multi Domain.
Please note that You need to create additional domain controllers. Each domain needs its own Domain Controller, you cannot create multiple domains using the same domain controller.
Each domain in Active Directory is identified by a (DNS) Domain Name System domain name and requires one or more domain controllers. If your network requires more than one domain, you can easily create multiple domains.
One or more domains that share a common schema and global catalog are referred to as a forest.
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