ZFS-inly server and dedicated ZIL

[Daniel Kalchev]

On 12.04.13 12:44, Dmitry Morozovsky wrote:
> No, this will be 8*SAS in 4 mirrored pairs + 2*SSD for mirrored ZIL and striped
> l2arc. Like the following (this is from other machine, but similar in setup):
>
>
>          NAME        STATE     READ WRITE CKSUM
>          pn          ONLINE       0     0     0
>            mirror-0  ONLINE       0     0     0
>              da0     ONLINE       0     0     0
>              da6     ONLINE       0     0     0
>            mirror-2  ONLINE       0     0     0
>              da1     ONLINE       0     0     0
>              da7     ONLINE       0     0     0
>          logs
>            mirror-1  ONLINE       0     0     0
>              da2d    ONLINE       0     0     0
>              da3d    ONLINE       0     0     0
>          cache
>            da2e      ONLINE       0     0     0
>            da3e      ONLINE       0     0     0
>
>

As already mentioned, multiple vdev zpool for root works just fine on 
FreeBSD. There is however one "restriction" -- all of the drives should 
be visible as BIOS drives at boot. If your BIOS (HBA SAS BIOS) supports 
that, then you should not expect problems.

Just make sure you test it with all the drives, before you build the pool.

On the other hand, using the same SSD for SLOG and L2ARC is not always 
good idea because those two have quite opposite requirements.

Daniel