Re: [Brahms-dev-l] File corruption on data21?

Hello.  I am not aware of file corruption in panasis disk.  Unlike other 
disks, panasis disk system keeps meta data as well as data.  This means 
you can recover files in case of disk failure.  (similar to the concept 
of RAID 5)  If you notice the file corruption soon enough, the meta data 
might be available. (???)  However, the panasis disk system is fairly 
new and it is still evolving.  Therefore, there might be still a few 
minor/major bugs around.  (And, that is a part of the reason RCF was 
able to get this disk system cheaper :) )   On the other hand, for all 
data disks, RCF does not guarantee recovery of data anyway.   It is 
assumed that data in data disks are something we can recreate.   If you 
want to keep data safe, I suggest to move them to HPSS. 

Hiro



Bjorn H Samset wrote:

>Hi dev' people. (This mail is mosly for Hiro and maybe Flemming, but it
>may be of general interest too.)
>
>This may be a known issue that I haven't caught, but in case it isn't: I'm
>having trouble with a number of root files stored on data21. I made a
>large number of trees for acceptance maps in march/april, but now about
>one in ten of them have developed problems. I can read the trees they
>contain up to a certain (random) point, and then ROOT crashes on the
>GetEntry() call. ROOT also crashes if I just try to project something out
>of the tree.
>
>I've tried with both new and old ROOT versions, so this seems to be a
>genuine problem with files that used to be fine. Have there been any other
>problems with file corruption on data21, or do you know of any other
>obvious reason for this? For me it's just a nuisance (I can remake files
>quickly) but it makes me a bit worried when files just stop working like
>that...
>
>Any ideas?
>
>Regards
>--Bjorn
>
>
>
>
>--
>Bjorn H. Samset                           Phone: 22856465/92051998
>PhD student, heavy ion physics            Adr:   P.b. 1048 Blindern
>Inst. of Physics, University of Oslo             0316 Oslo, Norway
>                              \|/
>----------------------------> -*- <-----------------------------
>                              /|\
>
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>


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