1SYSTEMD-COREDUMP(8)            systemd-coredump            SYSTEMD-COREDUMP(8)
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NAME

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

10       /usr/lib/systemd/systemd-coredump
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12       /usr/lib/systemd/systemd-coredump --backtrace
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14       systemd-coredump@.service
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16       systemd-coredump.socket
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DESCRIPTION

19       systemd-coredump@.service is a system service that can acquire core
20       dumps from the kernel and handle them in various ways. The
21       systemd-coredump executable does the actual work. It is invoked twice:
22       once as the handler by the kernel, and the second time in the
23       systemd-coredump@.service to actually write the data to the journal.
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25       When the kernel invokes systemd-coredump to handle a core dump, it runs
26       in privileged mode, and will connect to the socket created by the
27       systemd-coredump.socket unit, which in turn will spawn an unprivileged
28       systemd-coredump@.service instance to process the core dump. Hence
29       systemd-coredump.socket and systemd-coredump@.service are helper units
30       which do the actual processing of core dumps and are subject to normal
31       service management.
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33       Core dumps can be written to the journal or saved as a file. Once saved
34       they can be retrieved for further processing, for example in gdb(1).
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36       By default, systemd-coredump will log the core dump including a
37       backtrace if possible to the journal and store the core dump itself in
38       an external file in /var/lib/systemd/coredump.
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40       The behavior of a specific program upon reception of a signal is
41       governed by a few factors which are described in detail in core(5). In
42       particular, the core dump will only be processed when the related
43       resource limits are sufficient.
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45       It is also possible to invoke systemd-coredump with --backtrace option.
46       In this case, systemd-coredump expects a journal entry in the journal
47       Journal Export Format[1] on standard input. The entry should contain a
48       MESSAGE= field and any additional metadata fields the caller deems
49       reasonable.  systemd-coredump will append additional metadata fields in
50       the same way it does for core dumps received from the kernel. In this
51       mode, no core dump is stored in the journal.
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CONFIGURATION

54       For programs started by systemd process resource limits can be set by
55       directive LimitCore=, see systemd.exec(5).
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57       In order to be used by the kernel to handle core dumps,
58       systemd-coredump must be configured in sysctl(8) parameter
59       kernel.core_pattern. The syntax of this parameter is explained in
60       core(5). systemd installs the file /usr/lib/sysctl.d/50-coredump.conf
61       which configures kernel.core_pattern accordingly. This file may be
62       masked or overridden to use a different setting following normal
63       sysctl.d(5) rules. If the sysctl configuration is modified, it must be
64       updated in the kernel before it takes effect, see sysctl(8) and
65       systemd-sysctl(8).
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67       In order to by used in the --backtrace mode, an appropriate backtrace
68       handler must be installed on the sender side. For example, in case of
69       python(1), this means a sys.excepthook must installed, see
70       systemd-coredump-python[2].
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72       The behavior of systemd-coredump itself is configured through the
73       configuration file /etc/systemd/coredump.conf and corresponding
74       snippets /etc/systemd/coredump.conf.d/*.conf, see coredump.conf(5). A
75       new instance of systemd-coredump is invoked upon receiving every core
76       dump. Therefore, changes in these files will take effect the next time
77       a core dump is received.
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79       Resources used by core dump files are restricted in two ways.
80       Parameters like maximum size of acquired core dumps and files can be
81       set in files /etc/systemd/coredump.conf and snippets mentioned above.
82       In addition the storage time of core dump files is restricted by
83       systemd-tmpfiles, corresponding settings are by default in
84       /usr/lib/tmpfiles.d/systemd.conf.
85
86   Disabling coredump processing
87       To disable potentially resource-intensive processing by
88       systemd-coredump, set
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90           Storage=none
91           ProcessSizeMax=0
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93       in coredump.conf(5).
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USAGE

96       Data stored in the journal can be viewed with journalctl(1) as usual.
97       coredumpctl(1) can be used to retrieve saved core dumps independent of
98       their location, to display information and to process them e.g. by
99       passing to the GNU debugger (gdb).
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SEE ALSO

102       coredump.conf(5), coredumpctl(1), systemd-journald.service(8), systemd-
103       tmpfiles(8), core(5), sysctl.d(5), systemd-sysctl.service(8).
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NOTES

106        1. Journal Export Format
107           https://www.freedesktop.org/wiki/Software/systemd/export
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109        2. systemd-coredump-python
110           https://github.com/keszybz/systemd-coredump-python
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114systemd 243                                                SYSTEMD-COREDUMP(8)
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