[Lustre-discuss] Moving files off an OST

[Scott]

Appolgies if Im missing something obvious here.

My OSTs are set up in Raid 5 and one of the arrays has a bad stripe so i 
need to rebuild it.  In preparation for this i want to move all the data 
off of this OST so i deactivated the OST on the MDS and ran:


lfs find --recursive --obd nasone-OST0002_UUID --quiet /lustre | while 
read F;  cp $F $F.tmp && mv $F.tmp $F; done

This ran for quite a while and after it finished i ran the find command 
again to confirm there were no more files on the OST.

However if i look at the OSS i still show there are 3.4TBs of used space 
on that OST2:

# df
Filesystem           1K-blocks      Used Available Use% Mounted on

/dev/sdd             5765425880 5223515676 249043440  96% /mnt/ost4
/dev/sdc             4804519904 3479755816 1080708536  77% /mnt/ost2

Does this make any sense at all or am i missing something obvious here? 
I was expecting (hoping) to see the used space back to almost zero so 
does this mean i have quite a bit of lost data?

Any help?

Regards