Network/RaidUpgrade2024.md
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+<!--
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+vim: filetype=markdown
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+-->
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+
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+Requirements
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+============
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+* 10TB storage
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+* current usage is 8.4TB
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+
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+Options
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+=======
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+* (2+2)x 6TB, 12TB raid 10 = 12TB
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+* (2+4)x 6TB, 24TB raid 6
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+* (2+4)x 6TB, 18TB raid 10
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+* (2+2)x 6TB, 3x3TB raid 6
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+
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+Resources
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+=========
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+* [ZFS encryption vs ZFS+LUKS](https://raw.githubusercontent.com/jkool702/zfsEncryption_SpeedTest/main/ALL_RESULTS_SUMMARY)
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+
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+Configurations
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+==============
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+* H = Hot
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+* P = Parity
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+
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+Rebuild RAID6
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+-------------
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+* (1H + 2P + 6) x 3TB = 12TB usable out of 33TB
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+
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+RAID10
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+------
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+* 50% storage efficiency
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+* vs raid6
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+ * much faster resilver
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+ * less load
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+ * less risk of further failures
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+* not guaranteed to survive 2 disk failures
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+ * 4 disks: 33% failure
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+ * 6 disks: 20% failure
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+ * n disks: P(fail) = 1/n-1
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+* each pair should be 1 old and 1 new 6TB drive
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+
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+ZFS mirror vdev
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+---------------
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+* LUKS on top requires guest FS (so, ext4 again...)
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+* LUKS beneath requires individual encryption for each disk (blegh...)
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+* can stripe across pairs of different sizes (e.g. 4x6TB, 2x3TB = 15TB usable)
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+
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+Migration Strategy
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+==================
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+* duplicate mount of md6-media at /mnt/media
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+* migrate metadata and config
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+* unmount md6-media and mount ia/media in its place
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+* symlink /mnt/media as /mnt/md6-media
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+* symlink /mnt/home as /mnt/md6-home
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+* symlink /mnt/systems as /mnt/md6-media/systems