coredumpctl

Synopsis

coredumpctl [Options...] {COMMAND} [PID|COMM|EXE|MATCH...]

Description

coredumpctl is a tool that can be used to retrieve and process core dumps and metadata which were saved by systemd-coredump(8).

Commands

The following commands are understood:

list

List core dumps captured in the journal matching specified characteristics. If no command is specified, this is the implied default.

The output is designed to be human readable and contains list contains a table with the following columns:

TIME

The timestamp of the crash, as reported by the kernel.

PID

The identifier of the process that crashed.

UID, GID

The user and group identifiers of the process that crashed.

SIGNAL

The signal that caused the process to crash, when applicable.

COREFILE

Information whether the coredump was stored, and whether it is still accessible: "none" means the core was not stored, "-" means that it was not available (for example because the process was not terminated by a signal), "present" means that the core file is accessible by the current user, "journal" means that the core was stored in the "journal", "truncated" is the same as one of the previous two, but the core was too large and was not stored in its entirety, "error" means that the core file cannot be accessed, most likely because of insufficient permissions, and "missing" means that the core was stored in a file, but this file has since been removed.

EXE

The full path to the executable. For backtraces of scripts this is the name of the interpreter.

It's worth noting that different restrictions apply to data saved in the journal and core dump files saved in /var/lib/systemd/coredump, see overview in systemd-coredump(8). Thus it may very well happen that a particular core dump is still listed in the journal while its corresponding core dump file has already been removed.

info

Show detailed information about the last core dump or core dumps matching specified characteristics captured in the journal.

dump

Extract the last core dump matching specified characteristics. The core dump will be written on standard output, unless an output file is specified with --output=.

debug

Invoke a debugger on the last core dump matching specified characteristics. By default, gdb(1) will be used. This may be changed using the --debugger= option or the $SYSTEMD_DEBUGGER environment variable.

Options

The following options are understood:

-h, --help

Print a short help text and exit.

--version

Print a short version string and exit.

--no-legend

Do not print column headers.

--no-pager

Do not pipe output into a pager.

-1

Show information of a single core dump only, instead of listing all known core dumps.

-S, --since

Only print entries which are since the specified date.

-U, --until

Only print entries which are until the specified date.

-r, --reverse

Reverse output so that the newest entries are displayed first.

-F FIELD, --field=FIELD

Print all possible data values the specified field takes in matching core dump entries of the journal.

-o FILE, --output=FILE

Write the core to FILE.

--debugger=DEBUGGER

Use the given debugger for the debug command. If not given and $SYSTEMD_DEBUGGER is unset, then gdb(1) will be used.

-D DIR, --directory=DIR

Use the journal files in the specified DIR.

-q, --quiet

Suppresses informational messages about lack of access to journal files and possible in-flight coredumps.

Matching

A match can be:

PID

Process ID of the process that dumped core. An integer.

COMM

Name of the executable (matches COREDUMP_COMM=). Must not contain slashes.

EXE

Path to the executable (matches COREDUMP_EXE=). Must contain at least one slash.

MATCH

General journalctl match filter, must contain an equals sign ("="). See journalctl(1).

Exit Status

On success, 0 is returned; otherwise, a non-zero failure code is returned. Not finding any matching core dumps is treated as failure.

Environment

$SYSTEMD_DEBUGGER

Use the given debugger for the debug command. See the --debugger= option.

Examples

Example 1. List all the core dumps of a program named foo

# coredumpctl list foo

Example 2. Invoke gdb on the last core dump

# coredumpctl debug

Example 3. Show information about a process that dumped core, matching by its PID 6654

# coredumpctl info 6654

Example 4. Extract the last core dump of /usr/bin/bar to a file named bar.coredump

# coredumpctl -o bar.coredump dump /usr/bin/bar

See Also

systemd-coredump(8), coredump.conf(5), systemd-journald.service(8), gdb(1)

Referenced By

core(5), coredump.conf(5), journalctl(1), systemd-coredump(8), systemd.directives(7), systemd.index(7), systemd.journal-fields(7).