16.04 update freezing

[Alan Pope]

Hi,

On -two- three occasions my Pi2 running 16.04 snappy edge has not
rebooted properly after an update. Typically it freezes at "Starting
kernel...". If I pull the power cable out and plug back in, it boots
okay again.  What logs / data should I get from the device/card to
debug this? It's kinda frustrating to find myself with an unresponsive
remote device. As an example, I just got this update:-

ubuntu at localhost:~$ snappy list -v
Name                Date       Version                          Developer
canonical-pi2       2016-03-21 3.1                              canonical
canonical-pi2       2016-03-23 3.2                              canonical*
canonical-pi2-linux 2016-02-03 4.3.0-1006-3                     canonical
canonical-pi2-linux 2016-03-07 4.3.0-1006-6                     canonical
canonical-pi2-linux 2016-03-21 4.4.0-1004-raspi2+20160321.17-52 canonical!
canonical-pi2-linux 2016-03-21 4.4.0-1004-raspi2-20160321-05-25 canonical
owncloud            2016-03-21 9.0.0ubuntu1                     canonical*
ubuntu-core         2016-03-21 16.04+20160321.17-37             canonical!
ubuntu-core         2016-03-21 16.04-20160321-14-25             canonical
ubuntu-core         2016-03-02 16.04.0-11.armhf                 canonical
ubuntu-core         2016-03-03 16.04.0-12.armhf                 canonical
ubuntu-core         2016-03-07 16.04.0-13.armhf                 canonical
ubuntu-core         2016-03-08 16.04.0-14.armhf                 canonical
ubuntu-core         2016-03-08 16.04.0-15.armhf                 canonical
ubuntu-core         2016-02-03 16.04.0-7.armhf                  canonical
Reboot to use canonical-pi2-linux version 4.4.0-1004-raspi2+20160321.17-52.
Reboot to use ubuntu-core version 16.04+20160321.17-37.

ubuntu at localhost:~$ sudo reboot

It's been like this for some 15 minutes now:- http://imgur.com/zA8OwAF

Cheers,
-- 
Alan Pope
Community Manager

Canonical - Ubuntu Engineering and Services
+44 (0) 7973 620 164
alan.pope at canonical.com
http://ubuntu.com/