crash dump
also: core dump, kernel dump, vmcore, kdump
A snapshot of a system's memory and state saved to disk when the kernel crashes or panics, used for post-mortem debugging and analysis.
A crash dump (or core dump) captures the entire contents of RAM and CPU registers at the moment a system failure occurs. This allows developers and system administrators to analyze what went wrong without needing to observe the crash in real-time.
Linux can be configured to automatically save crash dumps using tools like kdump (kernel dump) or netdump. When a kernel panic occurs, the system writes memory contents to a reserved partition or network location, then either reboots or halts.
Example: After a kernel panic, administrators can use crash or gdb to examine the dump file, inspect stack traces, and identify which code caused the failure. This is essential for debugging driver issues, hardware problems, or kernel bugs that are difficult to reproduce.