Hi,

I am facing a peculiar issue where a system reboot sometimes & not always posts a crash in last output.

root     pts/0        Wed Dec  4 11:47   still logged in
reboot   system boot  Wed Dec  4 11:30 - 11:57  (00:26)
root     pts/0        Tue Dec  3 18:14 - crash  (17:16)
reboot   system boot  Tue Dec  3 10:03 - 11:57 (1+01:53)
root     pts/0        Mon Dec  2 18:03 - down   (15:56)
reboot   system boot  Mon Dec  2 11:19 - 10:00  (22:40)
root     pts/0        Sat Nov 30 17:22 - crash (1+17:57)
reboot   system boot  Sat Nov 30 10:36 - 10:00 (2+23:24)
root     pts/0        Fri Nov 29 17:35 - down   (16:56

I then created an alias - alias reboot='sync && sleep 3s && sync && sleep 3s && /usr/bin/systemctl reboot'

Dec 04 12:49:34 localhost.localdomain kernel: type=1131 audit(1575443974.870:149): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped Create Volatile Files and Directories.
Dec 04 12:49:34 localhost.localdomain kernel: type=1130 audit(1575443974.871:150): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system
Dec 04 12:49:34 localhost.localdomain kernel: type=1131 audit(1575443974.871:151): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system
Dec 04 12:49:34 localhost.localdomain kernel: type=1130 audit(1575443974.872:152): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system
Dec 04 12:49:34 localhost.localdomain kernel: type=1131 audit(1575443974.872:153): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped Import network configuration from initramfs.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped target Local File Systems.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounting /rsync-rootIncrBkps-rsyncLogs-etc/rsyncmirror...
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounting /run/user/0...
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounting /rsync-rootIncrBkps-rsyncLogs-etc/rsyncINCRFILES-BKPdir...
Dec 04 12:49:34 localhost.localdomain kernel: type=1130 audit(1575443974.874:154): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system
Dec 04 12:49:34 localhost.localdomain kernel: type=1131 audit(1575443974.874:155): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped Configure read-only root support.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounting /var/opt...
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounting /boot...
Dec 04 12:49:34 localhost.localdomain kernel: XFS (dm-0): Unmounting Filesystem
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounted /run/user/0.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounted /rsync-rootIncrBkps-rsyncLogs-etc/rsyncmirror.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounted /rsync-rootIncrBkps-rsyncLogs-etc/rsyncINCRFILES-BKPdir.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped target Swap.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Deactivating swap /dev/disk/by-label/swap...
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounted /var/opt.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Unmounted /boot.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped target Local File Systems (Pre).
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped Remount Root and Kernel File Systems.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped Create Static Device Nodes in /dev.
Dec 04 12:49:34 localhost.localdomain kernel: type=1130 audit(1575443974.900:156): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped Collect Read-Ahead Data.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopped Replay Read-Ahead Data.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Reached target Shutdown.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Stopping Monitoring of LVM2 mirrors, snapshots etc. using dmeventd or progress polling...
Dec 04 12:49:34 localhost.localdomain systemd[1]: Deactivated swap /dev/disk/by-path/pci-0000:04:00.0-scsi-0:0:0:0-part4.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Deactivated swap /dev/sda4.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Deactivated swap /dev/disk/by-uuid/78b0d524-dc7d-403f-ab42-b7318368a154.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Reached target Unmount All Filesystems.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Reached target Final Step.
Dec 04 12:49:34 localhost.localdomain lvm[2160]: 1 logical volume(s) in volume group "vg_stndby" unmonitored
Dec 04 12:49:34 localhost.localdomain systemd[1]: Starting Reboot...
Dec 04 12:49:34 localhost.localdomain systemd[1]: Shutting down.
Dec 04 12:49:34 localhost.localdomain systemd[1]: Hardware watchdog 'iTCO_wdt', version 0
Dec 04 12:49:34 localhost.localdomain systemd[1]: Set hardware watchdog to 10min.
Dec 04 12:49:34 localhost.localdomain kernel: watchdog: watchdog0: watchdog did not stop!
Dec 04 12:49:35 localhost.localdomain systemd-shutdown[1]: Syncing filesystems and block devices.
Dec 04 12:49:35 localhost.localdomain systemd-shutdown[1]: Sending SIGTERM to remaining processes...
Dec 04 12:49:35 localhost.localdomain systemd-journal[689]: Journal stopped

journal entries do not show any errors, but it is recorded as crash in
last since there's no entry of - shutdown system down - in last.

last records sometimes a proper shutdown, many times as crash even though 
the reboot is done similarly all the times.

What could be the issue or should I be concerned about it.

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