What Happens to Local Copies of Call Detail Records Files on Cisco Unified CM Subscribers

B.

In a Cisco Unified Communications Manager (CUCM) cluster, Call Detail Records (CDRs) are generated for all calls that traverse the system, and these records are stored locally on each CUCM subscriber node. The CDRs contain valuable information about the calls, including the caller/callee, call duration, call quality, etc.

To ensure that the CDR data is easily accessible for billing and analysis purposes, the CUCM subscribers periodically transfer their CDR files to the publisher node, which acts as the central repository for CDR data. The transfer process is typically scheduled to occur on a regular basis, such as daily or weekly.

Now, let's consider each option in turn:

A. They will be compressed and backed up. This option is partially correct. Before the CDR files are transferred to the publisher, they are typically compressed to reduce the amount of storage space required. However, the files are not backed up at this point.

B. They will be deleted. This option is incorrect. After the CDR files are transferred to the publisher, they are not immediately deleted from the subscriber nodes.

C. They will be deleted only after the subscriber received notification that the publisher has also deleted the correspondent files. This option is incorrect. There is no notification process in place for CDR file deletion. The subscriber nodes do not rely on the publisher to initiate the deletion of their local CDR files.

D. They will remain on the subscriber server until overwritten by new CDR files. This option is correct. After the CDR files are transferred to the publisher, they are kept on the subscriber nodes until they are overwritten by new CDR files. This allows for redundancy and ensures that the CDR data is available in case the publisher becomes unavailable.

E. They will be compressed and then stored on the subscriber servers. This option is incorrect. After the CDR files are compressed and transferred to the publisher, they are not stored on the subscriber nodes.

In summary, the correct answer is D. After the CDR files are transferred to the publisher, they remain on the subscriber nodes until overwritten by new CDR files.