Provided by: systemd-coredump_245.4-4ubuntu3.24_amd64 bug

NAME

       systemd-coredump, systemd-coredump.socket, systemd-coredump@.service - Acquire, save and
       process core dumps

SYNOPSIS

       /lib/systemd/systemd-coredump

       /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