Hi, > But unless your drive firmware is broken the drive with only ever give > the correct data or an error. Smart has a counter for blocks that have > gone bad and will be fixed pending a write to them: > Current_Pending_Sector. > > The only way the drive should be able to give you bad data is if > multiple bits toggle in such a way that the ECC still fits. Not really, I've disks which are *perfect* in smart sense and nevertheless I had mistmatch count. This was a SW problem, I think now fixed, in RAID-10 code. This means that, yes, there could be mismatches, without any warning, from other sources than disks. And these could be anywhere in the system. I already mentioned, time ago, a cabling problem which was leading to a similar result: wrong data on different disks, without any warning or error from the HW layer. That is why it is important to know *where* the mismatch occurs and, if possible, in which device component. If it is an empty part of the FS, no problem, if it belongs to a specific file, then it would be possible to restore/recreate it. Of course, a tool will be needed telling which file is using a certain block of the device. bye, -- piergiorgio -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
