November 3, 200817 yr Look at the attached screenshot on this post ... http://lime-technology.com/forum/index.php?topic=2666.msg21929#msg21929 The user has just run a parity build. unRAID is reporting that "Parity is Valid." It also indicates that a successful parity verification has been performed ("Last checked on ..."). A user would think it is time to pop open a cold one and celebrate! But there have been a number of real-world cases in which a parity check AFTER the parity build shows sync errors. (This may be due to incompatibe hardware, flakey drives, or in some cases it was never fully determined.) Although parity has been built and SHOULD be accurate, the only way to know for sure is to run a parity check. And contrary to the message on the screen, it has NOT been checked! Changing the status messages to say "Parity is Built", and indicating that a parity check HAS NEVER been performed (but should be) would keep new users from a premature feeling of security and encourage them to perform the next logical step of performing a full parity check.
November 3, 200817 yr It also might be worthwhile to consider two dates in the superblock. Displaying these would make the situation clearer as to the parity disks good. 1. when parity is actually built. i.e. derived from all drives and created fresh. 2. when parity is checked/verified. i.e. derived from when all drives are read and validated against the parity drive.
November 3, 200817 yr It also might be worthwhile to consider two dates in the superblock. Displaying these would make the situation clearer as to the parity disks good. 1. when parity is actually built. i.e. derived from all drives and created fresh. 2. when parity is checked/verified. i.e. derived from when all drives are read and validated against the parity drive. unRAID updates the parity check date in the superblock before the parity check starts. If it is cancelled, it still reports that the parity check was successful as of the date it was just started. It should update the parity check date AFTER completion of a parity check and not update it at all if it was cancelled. Joe L.
November 3, 200817 yr It also might be worthwhile to consider two dates in the superblock. Displaying these would make the situation clearer as to the parity disks good. 1. when parity is actually built. i.e. derived from all drives and created fresh. 2. when parity is checked/verified. i.e. derived from when all drives are read and validated against the parity drive. I stand corrected, There seem to already be two dates in the superblock. There is a ctime (creation time). not sure exactly what cases this gets updated. I.E. if parity is actually being re-created via check. I know I removed a drive and did a restore this weekend so the ctime points to that time. The update time points to when the parity generation completed. So ideally a time field of when parity is created/reconstructed and when it is updated via check (validated). I'll try and do a test later.. reading the code is taking a bit of time. So now I'm wondering if a parity create operating can be initiated
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