Bruce: The system generates a "syslog" text file per day stored at /var/log/. It archives all previous days indefinitely as syslog.1 then syslog.2 etc. You can easily examine these files and see the reboot at example: cat /var/log/syslog
You may have to uncompress older files. If the BBB did not reboot in that one day period, all that there will be in the "syslog" is the time stamps from systemd-timesyncd and a few DHCP activities. If it rebooted, there will be several hundred lines of booting "spew" for each reboot. If you are looking for a visual indication, I run the following script to turn off the four blue user LEDs. If they come back on autonomously, then the unit has rebooted. <code> #!/bin/sh # # killleds.sh -- kill all user LEDs echo none > /sys/class/leds/beaglebone\:green\:usr0/trigger echo none > /sys/class/leds/beaglebone\:green\:usr1/trigger echo none > /sys/class/leds/beaglebone\:green\:usr2/trigger echo none > /sys/class/leds/beaglebone\:green\:usr3/trigger echo 0 > /sys/class/leds/beaglebone\:green\:usr0/brightness echo 0 > /sys/class/leds/beaglebone\:green\:usr1/brightness echo 0 > /sys/class/leds/beaglebone\:green\:usr2/brightness echo 0 > /sys/class/leds/beaglebone\:green\:usr3/brightness </code> ==== On Sunday, August 9, 2015 at 11:38:15 AM UTC-5, Bruce Boyes wrote: > > Interesting thread, just back in town after a week on a river in central > Idaho where there is no connectivity (and I like it that way, though > HughesNet is available, but was actually down for several days last week). > I'm running Ubuntu 14.04. I had been arriving at a similar point after > having several 3.18 (I think, it was months ago) BBB Rev C and A5A systems > running htop for 90+ days. I too have noticed the dependency on the power > jack. One other possible detail about that: the Adafruit "5V" supplies seem > to never be actually 5V, they are always higher, and deliberately so. I > have several and they are typically 5.2, 5.3, or higher, and I have > wondered if this is an issue. This variance exceeds +5% on many supplies. > If I run off of the USB mini B power input from a monitor hub (I have a > number of older HP 1600x1200 ISP monitors with USB hubs built in) they are > right at 5V exactly and don't have the reboot issue. Recently I have been > buying 5V 1-2A switching wall warts from Digikey, name brands such as > Triad, in hopes that they are actually 5V. > > All my systems just have power, Ethernet, USB keyboard/mouse via RF > dongle, hdmi video, and are running Apache and htop. I have some FTDI USB > 3v3 serial adapters on the boot monitor port. > > I'm a Linux newbie but a hardware EE. I have a DSO, SPI and I2C analyzers, > etc, and some other tools at hand which I'd be happy to apply if helpful, > and have a handful of mostly Rev C BBB purchased from Allied and Newark. > > What is the best way to determine when reboots occur? Is there a log file > I can check? I'm meaning to write some simple test code which will time > stamp a file. Linux newbie like I said. > > Happy to test other distros. Ubuntu or Debian, perhaps I don't really > care. I started with Ubuntu since I run that on desktops and notebooks. > > Bruce > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
