November 26, 20232 yr Technically this isn't complete, depending on how you look at it. Having dual parity allows you to replace a single data disk while keeping single parity protection, but there could be an option to clone the still functioning replacement disk with just normal single parity in place and do the physical replacement in software any time while the clone is valid. The size limit of the second drive would necessarily be limited by parity, and the extent of space beyond the current partition would need to be zeroed and maintained until the smaller drive was removed, allowing the file system to be expanded to the new space. Functionally this would be the equivalent of allowing a modified RAID1 volume as a single array disk member, where each individual data disk could be protected as a RAID1 as well as being a member of the traditional array. @limetech, any chance this could be considered? It would give those folks with limited or no backups and single parity a safer way to replace array disks, as well as offering multiple hardware redundancy for more critical single volumes in huge traditional Unraid arrays. The only downside I can think of besides the amount of work needed in the md driver is the amount of explaining needed to get the concept across.
November 26, 20232 yr 1 hour ago, JonathanM said: Technically this isn't complete, depending on how you look at it. I asked to have it marked completed based on its 2014 creation date. I read this as solved by the presence of dual parity.
November 26, 20232 yr 1 minute ago, primeval_god said: I asked to have it marked completed based on its 2014 creation date. I read this as solved by the presence of dual parity. I agree, that's why I moved it. The situation could be improved for single parity though. Adding dual parity just to replace a drive without losing single drive failure protection seems overkill, but that's where we are.
November 26, 20232 yr 1 hour ago, JonathanM said: I agree, that's why I moved it. The situation could be improved for single parity though. Adding dual parity just to replace a drive without losing single drive failure protection seems overkill, but that's where we are. Its an interesting idea. Perhaps it deserves to be its own feature request.
November 27, 20232 yr 20 minutes ago, primeval_god said: Perhaps it deserves to be its own feature request. Nah, it's an enhancement to an already completed feature request. 😀
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