cgd + zfs

[Pouya Tafti <pouya+lists.9fans%nohup.io@localhost>]

(Apologies in case this is not the right mailing list.)

*tl;dr* Is it sensible to use zfs on top of cgd or are there drawbacks w.r.t. zfs expecting raw I/O?

(Too many) details follow.

I plan to re-purpose a circa 2012 Supermicro server for a cheap home NAS.  It comes with an LSI MegaRAID 9261-8i controller and 8x 1TB SAS HDDs.  I'm wondering--without any experience with zfs--whether it may be more flexible/future-proof than RAID, and am considering using it instead (undecided yet as to the optimal configuration but I'm thinking a pool of 2x sets in RAIDZ2 may be sensible, so I can replace a single set with bigger HDDs later on if I need to). 

I've read that zfs doesn't like fancy hardware controllers on its I/O path (incl. RAID and caching), so I plan to replace the MegaRAID with a cross-flashed IBM ServeRAID M1015 in HBA mode.

I also thought of using cgd(4) for full-disk encryption underneath zfs, but am wondering if it would similarly violate the raw disk I/O expectations of zfs.

Would really appreciate any advice or related experience regarding combining cgd and zfs.

Any other feedback or red flags with respect to the above setup would be very welcome too.

Many thanks,
Pouya