Headless server just got suspended by updating systemd
I am NOT starting another flamewar about systemd, but I was just
upgrading a headless system (an old T61p laptop which has no
functioning screen any more but which otherwise runs well and which I
use as an internal webserver) by running aptitude in an ssh session.
All went well until udev got upgraded, when I lost contact with the
server and could not ping it.
Looking at the laptop, I noticed that the suspend indicator was on,
even though I have had power management ignore the lid switch. I
opened the lid and it resumed. I was able again to ping and ssh into
the server. However, 'w' told me that the machine had been up for 85
days, which meant it was time to reboot. I did that - it took a VERY
long time to come back up, compared with how quickly it used to reboot
- but when I closed the lid, it suspended again.
It turns out that logind, a piece of systemd, has taken over power
management by default. Editing /etc/systemd/logind.conf so that it
contains "HandleLidSwitch=ignore" and restarting logind (with 'sudo
systemctl restart systemd-logind') has corrected the problem.
My situation is probably rather unusual and so others may not run into
the same problem, but just in case, this information may help.
which I found by Googling.