On Wed, 2014-01-29 at 14:39 +0100, Juan A. Sillero wrote: > Hello, > > We are a pioneering group in turbulence at the Polytechnic University of > Madrid (torroja.dmt.upm.es), running simulations in supercomputing > centers all around the world and hosting massive data in our data center > that are publicly accessible. > > Apparently we have lost one of our partitions of 20 Tb because of a > under-voltage error of a power source plus a disk failure and we are > trying to fix it, but it does not look good so far. > > The system is setup as follow: > XFS 6.1 > Raid 5 (12 x 2 disks of 2 Tb each) > Double disk controller managed by devmapper. > > What we know at this point is the next: > > 1) The topology of the disk is lost: the main-boot-record and the GPT > are corrupted. Are you sure the array had a main-boot-record and GPT ? What makes you think they are corrupted ? > 2) After running the testdisk utility we find 9 partitions instead of 1. There is a good chance that the discovered partitions are backup XFS superblocks; their location and content may allow you to figure out the array topology. > 3) With gdisk we have tried to create a new main-boot-record and GPT, > but it has not worked. This was a bad idea. Do you have a copy of the original data for these sectors ? > 4) We know that the blocksize is 4096 bytes, and the current capacity of > the raid is under 20 Tb, so we suspect that even if the disk-manager > says that the RAID is ok, it has not reconstructed the RAID after the > disk failing. > > We are stuck right now at this point, and help would be really > appreciated in order to bring up the partition. We will be pleased to > acknowledge the group in the upcoming publications. > > Thanks again, Juan A. Sillero > -- Roger Willcocks <roger@xxxxxxxxxxxxxxxx> _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
