Ubuntu 14.04 LTS on BBB

hello All,

every a few days of diligent work, my BBB loaded with Ubuntu 14.04 LTS vanishes.

No SSH access, no ping response.

How can I troubleshoot that?

The log in /var/log/syslog seems to be incomplete.
Many days are missing.

There is only an USB meteo sensor connected.

thanks for your time,


Milano, Italy