Seen similar behavior w/ Terastations.
If the system hasn't already, let it sit for approx 24 hours, and see if it's alive.
If not, give it a reboot. It'll likely be accessible for a short time and the issue might start occuring again.
If so, let it sit for approx 24 hours and see what happens.
Let us know if you've rebooted it or not (as the previous poster said).
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