On Mar 29, 2009, at 12:40, Frank Middleton wrote:
So what is best if you get a 4th drive for a 3 drive raidz? Is it better to keep it separate and use it for backups of the replaceable data (perhaps on a different machine), as a hot spare, second parity, or something else? Seems so un-green to have it spinning uselessly :-) LTO-4 tape drives at $200 just for the media? I guess not...
ZFS doesn't (at this time) support going from one RAID level to another dynamically. If you want to go from single-parity (RAID-Z) to dual-parity (RAID-Z2) you would need to destroy the pool and create it. If you don't to re-create it, hot spare I guess.
LTO-4 is closer to about US$ 60: http://www.tapeandmedia.com/lto_4_tape_ultrium_4_tapes_hp.asp http://www.cdw.com/shop/products/default.aspx?EDC=1225207 http://search.pricewatch.com/media/lto-4-0.htm Half-height SAS drives seem to be about US$ 3,000. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
