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SYSTEMD-COREDUMP(8)            systemd-coredump            SYSTEMD-COREDUMP(8)
NAME
       systemd-coredump, systemd-coredump.socket, systemd-coredump@.service -
       Acquire, save and process core dumps
SYNOPSIS
       /usr/lib/systemd/systemd-coredump
       /usr/lib/systemd/systemd-coredump --backtrace
       systemd-coredump@.service
       systemd-coredump.socket
DESCRIPTION
       systemd-coredump@.service is a system service that can acquire core
       dumps from the kernel and handle them in various ways. The
       systemd-coredump executable does the actual work. It is invoked twice:
       once as the handler by the kernel, and the second time in the
       systemd-coredump@.service to actually write the data to the journal.
       When the kernel invokes systemd-coredump to handle a core dump, it runs
       in privileged mode, and will connect to the socket created by the
       systemd-coredump.socket unit, which in turn will spawn an unprivileged
       systemd-coredump@.service instance to process the core dump. Hence
       systemd-coredump.socket and systemd-coredump@.service are helper units
       which do the actual processing of core dumps and are subject to normal
       service management.
       Core dumps can be written to the journal or saved as a file. Once saved
       they can be retrieved for further processing, for example in gdb(1).
       By default, systemd-coredump will log the core dump including a
       backtrace if possible to the journal and store the core dump itself in
       an external file in /var/lib/systemd/coredump.
       The behavior of a specific program upon reception of a signal is
       governed by a few factors which are described in detail in core(5). In
       particular, the core dump will only be processed when the related
       resource limits are sufficient.
       It is also possible to invoke systemd-coredump with --backtrace option.
       In this case, systemd-coredump expects a journal entry in the journal
       Journal Export Format[1] on standard input. The entry should contain a
       MESSAGE= field and any additional metadata fields the caller deems
       reasonable.  systemd-coredump will append additional metadata fields in
       the same way it does for core dumps received from the kernel. In this
       mode, no core dump is stored in the journal.
CONFIGURATION
       For programs started by systemd process resource limits can be set by
       directive LimitCore=, see systemd.exec(5).
       In order to be used by the kernel to handle core dumps,
       systemd-coredump must be configured in sysctl(8) parameter
       kernel.core_pattern. The syntax of this parameter is explained in
       core(5). systemd installs the file /usr/lib/sysctl.d/50-coredump.conf
       which configures kernel.core_pattern accordingly. This file may be
       masked or overridden to use a different setting following normal
       sysctl.d(5) rules. If the sysctl configuration is modified, it must be
       updated in the kernel before it takes effect, see sysctl(8) and
       systemd-sysctl(8).
       In order to by used in the --backtrace mode, an appropriate backtrace
       handler must be installed on the sender side. For example, in case of
       python(1), this means a sys.excepthook must installed, see
       systemd-coredump-python[2].
       The behavior of systemd-coredump itself is configured through the
       configuration file /etc/systemd/coredump.conf and corresponding
       snippets /etc/systemd/coredump.conf.d/*.conf, see coredump.conf(5). A
       new instance of systemd-coredump is invoked upon receiving every core
       dump. Therefore, changes in these files will take effect the next time
       a core dump is received.
       Resources used by core dump files are restricted in two ways.
       Parameters like maximum size of acquired core dumps and files can be
       set in files /etc/systemd/coredump.conf and snippets mentioned above.
       In addition the storage time of core dump files is restricted by
       systemd-tmpfiles, corresponding settings are by default in
       /usr/lib/tmpfiles.d/systemd.conf.
   Disabling coredump processing
       To disable potentially resource-intensive processing by
       systemd-coredump, set
           Storage=none
           ProcessSizeMax=0
       in coredump.conf(5).
USAGE
       Data stored in the journal can be viewed with journalctl(1) as usual.
       coredumpctl(1) can be used to retrieve saved core dumps independent of
       their location, to display information and to process them e.g. by
       passing to the GNU debugger (gdb).
SEE ALSO
       coredump.conf(5), coredumpctl(1), systemd-journald.service(8), systemd-
       tmpfiles(8), core(5), sysctl.d(5), systemd-sysctl.service(8).
NOTES
        1. Journal Export Format
           https://www.freedesktop.org/wiki/Software/systemd/export
        2. systemd-coredump-python
           https://github.com/keszybz/systemd-coredump-python
systemd 239                                                SYSTEMD-COREDUMP(8)