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Set the 'Call Diagnostics Enabled' parameter to 'Enabled Only When CDR Enabled Flag is True'.
Navigate to Cisco Unified Serviceability > Tools >System > Scheduler > CDR Load
Make Sure that Continuous Loading 24/7 checkbox is selected.
Now add an SFTP server/Billing Server where the files will be sent to. Navigate to Cisco Unified Serviceability > Tools > CDR Management > Add New Billing Server.
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