On Sun, May 15, 2011 at 3:56 PM, Lennart Poettering <mzerqung@xxxxxxxxxxx> wrote: >> 5) in old initscripts, there was /etc/init.d/halt with section for ups >> shutdown. With that script gone, was that functionality ported to systemd >> somehow? > > Well, any such code is just inherently broken. It *cannot* work. Such code has worked fine for more than ten years, and Fedora has shipped it for a long time as well. Did we ship code that could not ever have worked? <snip> > The point of UPS is to prevent data loss after all, > and if you turn off the power before the kernel dealt with reboot() you > invite data loss. At that point, all non-root filesystems are unmounted; / has been remounted read-only, which means the kernel has synced all dirty data, and waited for the writeback to finish. So reboot() only needs to write very little to the disks, if anything at all. The "UPS shutdown command" doesn't turn off the power immediately, the UPS shuts down after a delay, usually 30 seconds. 30 seconds was plenty to shut down the system properly even 10 years ago, and AFAIK it is still plenty today. Mirek -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel
