Explanation/Reference:
Explanation:
To configure a virtual SNR DN on Cisco Unified SCCP IP phones, perform the following steps:
Prerequisites
Cisco Unified CME 9.0 or a later version.
Restrictions
Virtual SNR DN only supports Cisco Unified SCCP IP phone DNs.

Virtual SNR DN provides no mid-call support.

Mid-calls are either of the following:
- Calls that arrive before the DN is associated with a registered phone and is still present after the DN is

associated with the phone.
- Calls that arrive for a registered DN that changes state from registered to virtual and back to registered.

Mid-calls cannot be pulled back, answered, or terminated from the phone associated with the DN.

State of the virtual DN transitions from ringing to hold or remains on hold as a registered DN.

References: http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucme/admin/configuration/guide/ cmeadm/cmesnr.html#pgfId-1012065