Just took a power outage on my unraid server, no one was writing or reading from the server during the power outage. Pairty check came back with no synch errors. Was I just lucky? I have an epson 1100c UPS but I don't have any idea how to connect the terminal part of the UPS to server to get it to automate shutdown process on power outage.

 

Kip

Just took a power outage on my unraid server, no one was writing or reading from the server during the power outage. Pairty check came back with no synch errors. Was I just lucky?

 

This is normal.  ReiserFS that unRAID uses is a journaling file system, that ensures that all writes will succeed even if interrupted, even across a loss of power.  You should not normally get parity errors, although you might have a corrupted or incomplete file, if interrupted during a write.  If you examine your next syslog after the power outage, near the bottom you will see a few transactions being replayed for each drive.  This is a normal operation, the journaling file system is 'catching up' on the delayed writes, of a little background housekeeping.

 

If your systems had been writing to the unRAID server, then you may have a corrupted file, and the next action depends entirely on what agent or application was doing the write.  If you were copying a file, then it is simpler, you identify which file and re-copy.  If it was an application, then it is much harder, if not near impossible, to figure out what was happening, and determine the best fix.

 

This is why a UPS is so strongly recommended, for any system with data storage.  A UPS should normally protect you completely from 80% to 90% of all power outages.  For the rest, it is great to have a communications link to your server that would initiate an orderly shutdown, but all of the work done in this community so far, has been for the APC line of UPS's.  I imagine there will be additional drivers/procedures found for other popular UPS units, but you may have to do the digging yourself for a less known UPS.  I personally had never heard of a UPS made by Epson, so I don't know if they have Linux support for shutdown software.

Sorry it wasn't an espon ups it's a OPTI-UPS Enhanced Series ES1000C 1000VA 700W 8 Outlets UPS   http://www.newegg.com/Product/Product.aspx?Item=N82E16842107113 I only use the unraid for data storage, so as long as nobody is transfering files to the server it will be fine it takes a hard power outage every once in and awhile.

 

The software says it works on Linux Red Hat 8 and 9 Fedora 2 ~ 6 SuSE 9 Mandrake 8  not really sure if that would work with unraid.