Comment by merlincorey
6 years ago
> ZFS partitions are also almost impossible to resize
I'm not sure you've actually used ZFS very much as any way I can see you could be meaning this, it is actually pretty straightforward and simple to resize partitions with ZFS pools and volumes within ZFS pools.
For example, if you mean that you have a root zpool on a device using only half the device, you just have to resize the partition and then turn on `autoexpand` for the pool.
We are talking about something resembling adding an extra disk to raid5. Can be easily done in mdadm raid, and then you just need to resize lvm, or whatever you run over it. Can not be done in zfs, not in raid5/6 mode
You're confusing extending vdevs with extending pools and stripes.
It's kind of apples to oranges, really.
FreeNAS documentation[0] makes it pretty clear.
In ZFS, you cannot add devices to a vdev after it has been created -- however, you CAN add more vdevs to a pool.
So basically, your complaint is that ZFS wants to have stripes of vdevs and that instead of adding 1 drive to a 3 drive RAID5 to make a 4 drive RAID5, you have to add 3 drives to a RAIDZ1 for a 6 drive RAIDZ+0 that is equivalent to a RAID50 on a hardware controller.
Yes, it's more enterprisey, but it's not especially more difficult and the result is different and perhaps better depending on your use case.