On Thu, Aug 03, 2006 at 07:25:19PM -0400, Russell Leighton wrote: > > If the software (filesystem like ZFS or database like Berkeley DB) > finds a mismatch for a checksum on a block read, then what? > > Is there a recovery mechanism, or do you just be happy you know there is > a problem (and go to backup)? ZFS readsthis block again from different mirror, and if checksum is right -- returns good data to userspace and rewrites failed block with good data. Note, that there could be multiple mirrors, either physically (like RAID1) or logically (blocks could be mirrored on different areas of the same disk; some files can be protected with multiple mirrors, some left unprotected without mirrors). -- Tomasz Torcz To co nierealne -- tutaj jest normalne. [email protected] Ziomale na życie mają tu patenty specjalne.
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