452 | High Availabilityw w w . d e l l . c o m | s u p p o r t . d e l l . c o m Trace LogDevelopers interlace messages with software code to track a the execution of a program. These messagesare called trace messages; they are primarily used for debugging and provide lower level information thanevent messages, which are primarily used by system administrators. FTOS retains executed trace messagesfor hardware and software and stores them in files (logs) on the internal flash.• NV Trace Log—contains line card bootup trace messages that FTOS never overwrites, and is stored ininternal flash under the directory NVTRACE_LOG_DIR.• Trace Log—contains trace messages related to software and hardware events, state, and errors. TraceLogs are stored in internal flash under the directory TRACE_LOG_DIR.• Crash Log—contains trace messages related to IPC and IRC timeouts and task crashes on line cards,and is stored under the directory CRASH_LOG_DIR.For more information on trace logs and configuration options, see:• C-Series Debugging and Diagnostics• E-Series TeraScale Debugging and Diagnostics• E-Series ExaScale Debugging and Diagnostics• S-Series Debugging and DiagnosticsCore DumpsA core dump is the contents of RAM being used by a program at the time of a software exception and isused to identify the cause of the exception. There are two types of core dumps: application and kernel.• The kernel is the central component of an operating system that manages system processors andmemory allocation and makes these facilities available to applications. A kernel core dump is thecontents of the memory in use by the kernel at the time of an exception.• An application core dump is the contents of the memory allocated to a failed application at the time ofan exception.System LogEvent messages provide system administrators diagnostics and auditing information. FTOS sends eventmessages to the internal buffer, all terminal lines, the console, and optionally to a syslog server. For moreinformation on event messages and configurable options, see Management.Hot-lock BehaviorFTOS Hot-lock features allow you to append and delete their corresponding CAM entries dynamicallywithout disrupting traffic. Existing entries are simply are shuffled to accommodate new entries.FTOS offers the following Hot-lock features:
