Results 1 to 2 of 2

Thread: (20.04) Ubuntu freezes upon powering off

  1. #1
    Join Date
    Nov 2014

    (20.04) Ubuntu freezes upon powering off

    Since upgrading to 20.04 from 18.04 I have a weird problem: I don't seem to be able to normally power off my Ubuntu. Whichever option I choose - UI or sudo poweroff - the system just freezes and I'm forced to perform a hard shutdown.

    How do I solve it?

  2. #2
    Join Date
    Mar 2010

    Re: (20.04) Ubuntu freezes upon powering off

    check the system log files to see what's holding it up. You can use journalctl -b -1 to see the dmesg log from the last boot. That's where I'd start.
    I've never used "poweroff". I typically use

    # cleanly shutdown the system.
    sudo shutdown now
    # cleanly shutdown the system and reboot
    sudo shutdown -r now

    # shutdown the system. Should close critical files, but not guaranteed
    sudo shutdown -h now
    I've seen this power off the system and not do so. Most of the time, it does power it off, IME.

    I think shutdown is tied into systemctl commands that do the same things. The systemctl manpage has sections about each, if you want the EXACT answer.
    For example,
               Shut down and halt the system. This is mostly equivalent to
               systemctl start --job-mode=replace-irreversibly
               --no-block, but also prints a wall message to all users. This
               command is asynchronous; it will return after the halt operation is
               enqueued, without waiting for it to complete. Note that this
               operation will simply halt the OS kernel after shutting down,
               leaving the hardware powered on. Use systemctl poweroff for
               powering off the system (see below).
               If combined with --force, shutdown of all running services is
               skipped, however all processes are killed and all file systems are
               unmounted or mounted read-only, immediately followed by the system
               halt. If --force is specified twice, the operation is immediately
               executed without terminating any processes or unmounting any file
               systems. This may result in data loss. Note that when --force is
               specified twice the halt operation is executed by systemctl itself,
               and the system manager is not contacted. This means the command
               should succeed even when the system manager has crashed.
    Probably more details than you can to know. There are more for other options.

Tags for this Thread


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts