Both / All THREE Terastations shut down??? HELP PLEASE

[wumpus459]

Hi everyone.
I have two 5800D 16GB Terastations (lets call them A and B each 24 GB) and one 5800DWS Teratation 36GB (C). All Raid 5.

Im trying to Backup A and B to C.

This works but it has sofar never run to completion. The rsync backup kept stopping because "the network was lost" A and B could no longer reach C for some reason.
So I connected the three stations together with their own little 1GB switch and that seems to work much better.

Problem: the other day 2 weeks ago I came in and the backup still wasnt finished because A had powered down. Odd I thought, started it again and tried again. Three days later in the morning it was off again. I started it.
Now, four days later on a monday morning BOTH A and B are powered down (and not completeing their backups).

I know there are several "Auto Power Down" issues that Ive read about in these forums but I find it odd that first I dont have any such issues, then suddenly with one Terastation and now with both??

Things ive tried:
(1) There seems to be no "Auto Power Switch" on the back of the Terastation 5800D. There is a little switch on the back but its not marked "Auto Power". I never touched those switches (but now I switched them both once just for good measure).
(2) The Auto Sleep Modes on both devices are totally disabled.
(3) Today I updated the firmware to the latest version Firmware-Version：   3.42-0.01
(4) Terastation A is rather full. Before the powerdown the backup seemd to finish abnormally after 4 days (18TB) with the following rsync message:

Error    The "code 24" is in the log.
Causes    - A backup process was terminated abnormally.
- When the backup was started, the backup source file was edited with software which creates a tmp (temporarily) file, such as Word and Excel.
Solutions    - Do not edit a backup source file during a backup job.
Example of a log    rsync error: some files vanished before they could be transferred (code 24) at main.c(702)
rsync warning: some files vanished before they could be transferred (code 24) at main.c(702)

(5) The backup of (B) simply stopped in the middle of the backup log without errors (presumably because B went into standby mode/off)

Any ideas? What must I do to stop these from powering down?
I dont think its a plug issue. Its in a climatised Computerroom where i never had an electricity issue and we run lots of servers in there.

Any help appreciated,
Wumpus

[wumpus459]

Hi...I seem to be going nuts....

After my post, last night, while I was sound asleep, ALL THREE of my Terastations rebooted at 5:29 AM.

Does anyone have any ideas what this might be?

I will now put them on a seperate powersupply.

Thanks
Wumpus
ps - please can someone pinch me? What on earth could this be? I have no other outages in my computerroom.