systemd-pstore.service(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | CONFIGURATION | USAGE | SEE ALSO | COLOPHON

SYSTEMD-PSTORE.SERVICE(8)systemd-pstore.serviceSYSTEMD-PSTORE.SERVICE(8)

NAME         top

       systemd-pstore.service, systemd-pstore - A service to archive
       contents of pstore

SYNOPSIS         top

       /usr/lib/systemd/systemd-pstore

       systemd-pstore.service

DESCRIPTION         top

       systemd-pstore.service is a system service that archives the
       contents of the Linux persistent storage filesystem, pstore, to
       other storage, thus preserving the existing information contained
       in the pstore, and clearing pstore storage for future error
       events.

       Linux provides a persistent storage file system, pstore, that can
       store error records when the kernel dies (or reboots or
       powers-off). These records in turn can be referenced to debug
       kernel problems (currently the kernel stores the tail of the
       kernel log, which also contains a stack backtrace, into pstore).

       The pstore file system supports a variety of backends that map
       onto persistent storage, such as the ACPI ERST and UEFI
       variables. The pstore backends typically offer a relatively small
       amount of persistent storage, e.g. 64KiB, which can quickly fill
       up and thus prevent subsequent kernel crashes from recording
       errors. Thus there is a need to monitor and extract the pstore
       contents so that future kernel problems can also record
       information in the pstore.

       The pstore service is independent of the kdump service. In cloud
       environments specifically, host and guest filesystems are on
       remote filesystems (e.g. iSCSI or NFS), thus kdump relies
       (implicitly and/or explicitly) upon proper operation of
       networking software *and* hardware *and* infrastructure. Thus it
       may not be possible to capture a kernel coredump to a file since
       writes over the network may not be possible.

       The pstore backend, on the other hand, is completely local and
       provides a path to store error records which will survive a
       reboot and aid in post-mortem debugging.

       The systemd-pstore executable does the actual work. Upon
       starting, the pstore.conf file is read and the /sys/fs/pstore/
       directory contents are processed according to the options. Pstore
       files are written to the journal, and optionally saved into
       /var/lib/systemd/pstore/.

CONFIGURATION         top

       The behavior of systemd-pstore is configured through the
       configuration file /etc/systemd/pstore.conf and corresponding
       snippets /etc/systemd/pstore.conf.d/*.conf, see pstore.conf(5).

   Disabling pstore processing
       To disable pstore processing by systemd-pstore, set

           Storage=none

       in pstore.conf(5).

   Kernel parameters
       The kernel has two parameters,
       /sys/module/kernel/parameters/crash_kexec_post_notifiers and
       /sys/module/printk/parameters/always_kmsg_dump, that control
       writes into pstore. The first enables storing of the kernel log
       (including stack trace) into pstore upon a panic or crash, and
       the second enables storing of the kernel log upon a normal
       shutdown (shutdown, reboot, halt). These parameters can be
       managed via the tmpfiles.d(5) mechanism, specifically the file
       /usr/lib/tmpfiles/systemd-pstore.conf.

USAGE         top

       Data stored in the journal can be viewed with journalctl(1) as
       usual.

SEE ALSO         top

       pstore.conf(5)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have
       a bug report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2021-06-20.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2021-06-19.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 249                                    SYSTEMD-PSTORE.SERVICE(8)

Pages that refer to this page: pstore.conf(5)systemd.directives(7)systemd.index(7)