i'm able to create raidz with diff sized of hard disk. where im missing?

Question

i read about raidz5 cannot create with diff sizes of hard disks but i'm able to create raidz with diff sized of hard disk please tell me where im missing?

da0              0:107  12G zfs                                   - -
da1              0:109 8.0G zfs                                   - -
md0              0:13  456M ufs                                   - /
vtbd0            0:53   80G GPT                                   - /
  vtbd0p1        0:115 512K freebsd-boot       gptid/681ee6a8-6ab8-11eb-b72e-558e06157d17 -
  <FREE>         -:-   492K -                                     - -
  vtbd0p2        0:122 2.0G freebsd-swap                  gpt/swap0 -
  vtbd0p3        0:127  78G freebsd-zfs                   gpt/disk0 <ZFS>
  <FREE>         -:-   1.0M -                                     - -

  pool: edjstorage
 state: ONLINE
  scan: none requested
config:

    NAME         STATE     READ WRITE CKSUM
    edjstorage   ONLINE       0     0     0
      raidz1-0   ONLINE       0     0     0
        vtbd0p3  ONLINE       0     0     0
        da0      ONLINE       0     0     0
        da1      ONLINE       0     0     0

What does `zpool list` give as the size? – Richard Smith Feb 09 '21 at 13:55 — Richard Smith, Feb 09 '21 at 13:55

score 1 · Accepted Answer · answered Feb 09 '21 at 16:47

You are missing the fact that the various component devices used size will be rounded down to the smallest capacity - ie: supposing you create a RAIDZ with 3x 2TB disks and 1x 1TB disk, total pool capacity (including parity overhead) will be 4x 1TB (or 3TB excluding parity).

Similarly, a 2-way mirror between 1x 2TB disk and 1x 1TB disk will end with only 1TB usable capacity.

i'm able to create raidz with diff sized of hard disk. where im missing?

1 Answers1