On 05/18/2011 04:04 PM, Lennart Poettering wrote: > Host requests power down from UPS in 30s. Host then continues shut > down. If the host now ends up taking more time then expected for > shutting down it might still be busy at the time of the power going > away. It's a race between "UPS powering off" and "system finishing > shutdown". It's a bet that your system is faster than 30s when > unmounting the remaining file systems, syncing the MD/DM metadata to > disk, syncing ATA and so on (i.e. all the stuff the kernel does when you > invoke the reboot() syscall). Here's another race. Host requests power down from UPS in 30s. Host completes shutdown. At some point during that 30s interval, commercial power is restored. Result: Host shuts down and never restarts. Sorry about that. The way I've always prevented that is to have the host do a reboot, not a shutdown, but send an immediate shutdown command to the UPS just before sending control to the BIOS for the reboot. -- Bob Nichols "NOSPAM" is really part of my email address. Do NOT delete it. -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel