The actual configuration you need depends on what you want the auto-attendant to do. High-level:
In CUCM, create a CTI route point (e.g., "TransferVM" or "AutoAttendant"). Assign the directory number you want to use and the appropriate voicemail profile. Configure the line to call forward all to VM.
In Unity Connection, create a Call Handler and assign the extension as the directory number of the CTI route point. From there, you configure the caller input and other options as required for the Auto Attendant.
There are a number of posts within the forum that provide guidance on setting up different types of call handler options - ultimately, it really does depend on your specific needs.
Hailey
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