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Which is better RaidZ or mirror vdevs for ZFS?
ZFS: You should use mirror vdevs, not RAIDZ. – JRS Systems: the blog ZFS: You should use mirror vdevs, not RAIDZ. Continuing this week’s “making an article so I don’t have to keep typing it” ZFS series… here’s why you should stop using RAIDZ, and start using mirror vdevs instead. A pool is a collection of vdevs.
Can a ZFS pool be converted to a mirror?
Should automatically convert the pool to a mirror. I didn’t think I’d be answering my own question, but after much googling and spinning up a vagrant box with multiple disks to experiment with, I found how to create a degraded zfs mirror (raid1) pool.
How to convert one-disk ZFS pool into two-disk?
I have a one-drive zfs pool named data on my desktop computer, created with something like zpool create data /dev/mapper/data (zfs on luks). I would like to convert it into a raid1 pool, but only have 1 more drive to play with, and one more slot in my machine.
Do you have to run ZFS in RAID mode?
Note that ZFS does not have to run in RAID mode. You can just use individual disks. However, virtually 99% of people run ZFS for the RAID portion of it. You could just run your disks in striped mode, but that is a poor use of ZFS. Like other posters have said, ZFS wants to know a lot about the hardware.
How many TB of storage does a ZFS need?
However, this is not a “stripe” like you see in RAID10 – it’s just distribution of writes. If you make a RAID10 out of 2 2TB drives and 2 1TB drives, the second TB on the bigger drives is wasted, and your after-redundancy storage is still only 2 TB.
Why do I need ZFS for my home NAS?
This is the key limitation of ZFS as seen from the perspective of home NAS builders. To expand the storage capacity of your pool, you need to add extra VDEVs. And because each VDEV needs to take care of its own redundancy, you also need to buy extra drives for parity.
Is it better to use ZFS or mdadm?
With ZFS, you either have to buy all storage you expect to need upfront, or you will be wasting a few hard drives on redundancy you don’t need. This fact is often overlooked, but it’s very important when you are planning your build. Other software RAID solutions like Linux MDADM lets you grow an existing RAID array with one disk at a time.