I have a pi logging temperature, it runs 24/7, attached to Ethernet and power only (with a DS18B20 sensor on GPIO pins). It runs Wheezy Raspbian, the 2012-09-18 image from raspberrypi.org.
$ uname -a
Linux raspberrypi 3.2.27+ #160 PREEMPT Mon Sep 17 23:18:42 BST 2012 armv6l GNU/Linux
Recently I noticed it was not responding to HTTP requests nor to SSH. The PWR LED was on but nothing else I think.
After cycling power a few times and taking it to a HDMI TV I was able to get it restarted and reconnected to Ethernet.
There was a gap in the temperature log file (and graphs) from 07:20 in 22nd which makes me sure the CPU was either locked or not running cron
Here's syslog from around that time
Jan 22 07:30:07 raspberrypi kernel: [2630231.999840] ERROR::dwc_otg_hcd_urb_enqueue:477:
Not connected
Jan 22 07:30:07 raspberrypi kernel: [2630231.999854]
Jan 22 07:30:07 raspberrypi kernel: [2630231.999941] ERROR::dwc_otg_hcd_urb_enqueue:477: Not connected
Jan 22 07:30:07 raspberrypi kernel: [2630231.999951]
Jan 22 07:30:07 raspberrypi kernel: [2630231.999977] ERROR::dwc_otg_hcd_urb_enqueue:477: Not connected
Jan 22 07:30:07 raspberrypi kernel: [2630231.999986]
Jan 22 07:30:07 raspberrypi kernel: [2630232.210581] usb 1-1: USB disconnect, device number 12
Jan 22 07:30:07 raspberrypi kernel: [2630232.210608] usb 1-1.1: USB disconnect, device number 13
Jan 22 07:30:07 raspberrypi kernel: [2630232.210814] smsc95xx 1-1.1:1.0: eth0: unregister 'smsc95xx' usb-bcm2708_usb-1.1, smsc95xx USB 2.0 Ethernet
Jan 22 07:30:07 raspberrypi kernel: [2630232.380696] Indeed it is in host mode hprt0 = 00021501
Jan 22 07:30:07 raspberrypi kernel: [2630232.590622] usb 1-1: new high-speed USB device number 14 using dwc_otg
Jan 22 07:30:07 raspberrypi kernel: [2630232.590798] Indeed it is in host mode hprt0 = 00001101
Jan 22 07:30:07 raspberrypi ifplugd(eth0)[24688]: Link beat lost.
Jan 22 07:30:07 raspberrypi ifplugd(eth0)[24688]: Exiting.
Jan 22 07:30:08 raspberrypi kernel: [2630232.800736] usb 1-1: New USB device found, idVendor=0424, idProduct=9512
Jan 22 07:30:08 raspberrypi kernel: [2630232.800766] usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
Jan 22 07:30:08 raspberrypi kernel: [2630232.811918] hub 1-1:1.0: USB hub found
Jan 22 07:30:08 raspberrypi kernel: [2630232.812058] hub 1-1:1.0: 3 ports detected
Jan 22 07:30:08 raspberrypi kernel: [2630233.090644] usb 1-1.1: new high-speed USB device number 15 using dwc_otg
Jan 22 07:30:08 raspberrypi kernel: [2630233.191045] usb 1-1.1: New USB device found, idVendor=0424, idProduct=ec00
Jan 22 07:30:08 raspberrypi kernel: [2630233.191088] usb 1-1.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
This sort of set of messages repeats.
Since it's Ethernet interface was down, it wasn't updating time, so it's hard to separate the log records on 22nd from subsequent boots. Until I reset date on 24th 21:00 it thought it was still 22nd 07:30 ish. (Must buy RTC).
The stuff about "dwc_otg_hcd_urb" looks suspicious
Can anyone suggest what might have caused the lockup?
