/mcpIf the value of the CDR Log Calls With Zero Duration Flag parameter is True, the system writes all calls to a flat file. For more information, see Configuring CDR Service Parameters section in this book. Note Call Information Record Types Unified Communications Manager generates two different types of call information records: Call Detail Records (CDRs) and Call Management Records (CMRs), also called call diagnostic records. CDRs store information about the endpoints of the call and other call control/routing aspects. CMRs contain diagnostic information about the quality of the streamed audio of the call. More than one CMR can exist per CDR. CMRs are supported by Cisco Unified IP Phones, Cisco 7960 series phones, and Media Gateway Control Protocol (MGCP) gateways. If one of these endpoints is involved in a call, it will generate a CMR record after the call terminates. Each endpoint in the call generates a separate CMR record. If the call involves endpoints that do not support call diagnostics, no record gets generated for that endpoint. A call from a Cisco7960 phone to an H.323 gateway generates one CMR record (from the Cisco 7960 phone). CDRs relate to the CMRs via two globalCallID columns: • globalCallID_callManagerId • globalCallId_callId When the Call Diagnostics service parameter is set to True, the system generates up to two CMRs for each call. Each type of call, such as conference calls, call transfers, forwarded calls, and calls through gateways, produce a set of records that get written to ASCII files at the end of the call. Only completed calls and failed calls generate CDRs and CMRs. Unified Communications Manager does not perform any post-processing on CDRs or CMRs. Global Call Identifier The Unified Communications Manager allocates a global call identifier (GlobalCallID_callId) each time that a Cisco Unified IP Phones is taken off the hook or a call is received from a gateway. The GlobalCallID_callId is allocated sequentially on a Unified Communications Manager server, independent of calls running on other call servers in the cluster. Unified Communications Manager writes the GlobalCallID_callId value to a disk file for every 1,000th call. When Unified Communications Manager restarts for any reason, it assigns the next 1000th number to the next GlobalCallID_callId. For example, when a successful call gets made, the GlobalCallID_callId value in the CDR specifies 1001. For the next call, the GlobalCallID_callId value specifies 1002, and so on. When Unified Communications Manager restarts, the value for the next call in the CDR gets assigned 2001. The numbers continue sequentially from there until Unified Communications Manager restarts again. For the next restart, the GlobalCallID_callId value specifies 3001. The maximum value that gets assigned to the GlobalCallID_callId is limited to 24 bits. When this limitation occurs, the GlobalCallID_callId value gets reset to 1. Note Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs 207 CDR Records Call Information Record Types