I am running Ubuntu server 16.04 on an old laptop. I have had consistent problems for several months with it falling asleep: it will drop its network connection (I am not using wifi) and from the lack of fan noise, I can tell it also stops working on the distributed computing projects I have it do. Up until a few days ago it would go up to ten days or so without falling asleep, but now it is almost every day. Previously, I wrote a cron job to ping Google regularly to keep the computer awake, but it does not seem to have helped. Below is a recent syslog entry. The 8:44 events are me manually restarting the laptop. Why do the entries just stop? What does the

@^@^@^@

mean?

I do not believe my problems are due to, say, closing the lid, as I have set systemd to ignore that. Here is a log excerpt: