Post B4aCR27lMaWX9Tlcau by mwl@io.mwl.io
 (DIR) More posts by mwl@io.mwl.io
 (DIR) Post #B4aBoZzrUZfkubjeIS by yehor@mastodon.glitchy.social
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       "ZFS with a striped configuration can be more space-efficient compared to other setups like RAIDZ, as it does not require additional space for parity. However, the actual usable space will depend on the number of disks and the specific configuration used."With this in mind, I started to migrate data from striped #zpool to #Raidz1 There was around 10TB of data to move. But after moving all that data, it took around 20TB on a two-drive raidz1. Some #BlackMagicFuckery #zfs #nas #homelab
       
 (DIR) Post #B4aBoaHwPM8NogC5Tc by DrHyde@fosstodon.org
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       @yehor I didn't even think that a two drive raidz1 was possible! Good to know for when I start migrating, thanks!
       
 (DIR) Post #B4aBoaVPbGuSUSUqTQ by yehor@mastodon.glitchy.social
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       @DrHyde yeah, that was a surprise for me as well. But you have no redundancy with two drives.
       
 (DIR) Post #B4aBoahor8pn6wIkoS by DrHyde@fosstodon.org
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       @yehor if it was traditional raid then that's the case, but is it with a two disk raidz1? You don't really have a data drive and a parity drive, you have two disks with checksums and can always tell which block is buggered because it will fail the checksum.
       
 (DIR) Post #B4aBoasoCHcnf1RWwS by yehor@mastodon.glitchy.social
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       @DrHyde hm.... I'm not sure. Maybe this is the reason why my 10 TB of data took 20 TB on the raidz1?
       
 (DIR) Post #B4aBob0bjHra3D5l68 by DrHyde@fosstodon.org
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       @yehor yes, it is. An N disk RAID (whether traditional RAID or raidz) with P disks worth of parity/redundancy will have N-P disks worth of usable space. So with 2 disks, and 1 disk worth of redundancy, you've got 1 disk worth of space.
       
 (DIR) Post #B4aBob35a3qeAuFjxw by yehor@mastodon.glitchy.social
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       Striped poll consists of two drives as well. At the end, I should have #Raidz1 poll with 4 drives. Finally, having the same size.#homelab #zfs #zpool #nas
       
 (DIR) Post #B4aBobAt745QZ5ty7c by DrHyde@fosstodon.org
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       @yehor At this point I should ask @mwl to check my thinking because I've never actually used a raidz with so few devices :-) His ZFS book is excellent.
       
 (DIR) Post #B4aBobPQF1iFIAhZmC by mwl@io.mwl.io
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       @DrHyde @yehor two drive raidz1 has zero redundancy. Are you sure it's not a mirror?I'd be curious to see "zpool status -v poolname"
       
 (DIR) Post #B4aC7xXOBz6XQNesnQ by yehor@mastodon.glitchy.social
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       @mwl  I'm sure. I also was sure there is no redundancy on a two-drive raidz1 until @DrHyde's comment ))Here is the output. It is in the process of adding the third drive.
       
 (DIR) Post #B4aCR27lMaWX9Tlcau by mwl@io.mwl.io
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       @yehor @DrHyde I'm gonna have to play with this and see what's going on, thanks