systemd-coredump is not consistent in dumping systemd service cores

This document (7017378) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 12 Service Pack 1 (SLES 12 SP1)
SUSE Linux Enterprise Server 12

Situation

When systemd services core dump or are forced to core dump, their core files are not always written to the journal for review. The following sequence of commands shows the issue.


sles12:~ # sysctl -a | grep kernel.core_pattern
kernel.core_pattern = |/usr/lib/systemd/systemd-coredump %p %u %g %s %t %e

sles12:~ # systemd-coredumpctl list
No coredumps found

sles12:~ # systemctl kill --signal SIGABRT cron

sles12:~ # systemd-coredumpctl list
No coredumps found

sles12:~ # systemctl kill --signal SIGABRT cron

sles12:~ # systemd-coredumpctl list
TIME                                         PID   UID   GID SIG EXE
              Thu 2016-03-17 11:24:07 MDT   1660     0     0   6 /usr/sbin/cron

sles12:~ # systemctl kill --signal SIGABRT cron

sles12:~ # systemd-coredumpctl list
TIME                                         PID   UID   GID SIG EXE
              Thu 2016-03-17 11:24:07 MDT   1660     0     0   6 /usr/sbin/cron
              Thu 2016-03-17 11:24:17 MDT   1666     0     0   6 /usr/sbin/cron

sles12:~ # systemctl kill --signal SIGABRT cron

sles12:~ # systemd-coredumpctl list
TIME                                         PID   UID   GID SIG EXE
              Thu 2016-03-17 11:24:07 MDT   1660     0     0   6 /usr/sbin/cron
              Thu 2016-03-17 11:24:17 MDT   1666     0     0   6 /usr/sbin/cron
              Thu 2016-03-17 11:24:26 MDT   1672     0     0   6 /usr/sbin/cron

sles12:~ # systemctl kill --signal SIGABRT cron

sles12:~ # systemd-coredumpctl list
TIME                                         PID   UID   GID SIG EXE
              Thu 2016-03-17 11:24:07 MDT   1660     0     0   6 /usr/sbin/cron
              Thu 2016-03-17 11:24:17 MDT   1666     0     0   6 /usr/sbin/cron
              Thu 2016-03-17 11:24:26 MDT   1672     0     0   6 /usr/sbin/cron

The cron.service was killed five times, yet only three core dumps were written to the systemd journal.

Resolution

The is a known issue that has been fixed. Update the systemd package.

SLES12 SP0: systemd-210-70.39.1 or later.
SLES12 SP1: systemd-210-95.1 or later.

Disclaimer

This Support Knowledgebase provides a valuable tool for SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented "AS IS" WITHOUT WARRANTY OF ANY KIND.