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I'm using Ubuntu 14.04 with Gnome as primary window manager (not Ubuntu Gnome, just installed Gnome after Ubuntu). I often tend to use pm-hibernate to get into hibernation, but when I boot again the resume sometimes, but not always, fails and the computer reboots. At the second boot, the GRUB bootloader screen won't countdown the timer anymore and it will wait for my input. I'd really like to analyze why this is happening, but I don't even know in which log file to look for "resume errors" or where to start. Can you give me a hint on this?
About a year ago it all worked very well, but suddenly (I don't know when exactly) that all started and I don't know what I have changed to make this happen.