[OpenIndiana-discuss] What to do with 4k sector SATA drives... All fixes are for SCSI drives only!!??

[Reginald Beardsley]

--- On Sun, 3/17/13, Hans J Albertsson <hans.j.albertsson at branneriet.se> wrote:

> From: Hans J Albertsson <hans.j.albertsson at branneriet.se>
> Subject: Re: [OpenIndiana-discuss] What to do with 4k sector SATA drives... All fixes are for SCSI drives only!!??
> To: "Discussion list for OpenIndiana" <openindiana-discuss at openindiana.org>
> Date: Sunday, March 17, 2013, 1:31 PM
> I read somewhere that you can
> 
> Set sata to ahci in bios.
> Boot a live dvd
> In there  i can just do a zpool import -f rpool.
> Could this be true? Really?

4k sector SATA drives work fine w/ the sd.conf configured properly.  Make sure you read George Wilson's blog on the subject:

http://blog.delphix.com/gwilson/2012/11/15/4k-sectors-and-zfs/

In particular, the part about using cfgadm to reattach and reconfigure the the disk.  4k USB disks don't appear to work properly at present, though they do work, albeit slowly.


Some operations are a bit like a "Towers of Hanoi" problem.  You might get some insight into the situation from my exposition on building a bootable, 3-4 drive RAIDZ using the GUI installer.

http://wiki.openindiana.org/oi/Building+a+small+NAS+using+OI

That's gotten a bit confused between my edits and Jim's.  I think all the info is there, just not very well organized.  I had lots of trouble until I wrote a step by step outline (one sheet of paper).  That was sufficient to get me there.

Probably the safest approach would be to remove the existing drives, install the 4k drive and install onto it.  Then replace the old drives and import the old pools, copy the data and then reconfigure the interfaces and build new pools on the old drives.

You *might* be able to form a mirror w/ 512 and 4k drives,  but I'd test that w/ a fresh install onto a 512 sector disk rather than a system I wanted to keep stuff from.  There are warnings about that not working, but it might work as a migration pathway.

For example:

install and configure 4k drive

form mirror w/ 512 sector drive

wait for it to resilver

detach 512 sector drive from mirror

install another 4k drive

form mirror w/ pair of 4k drives


NB: format(1m) will create a cylinder that doesn't start on a 4k boundary, however, it would appear that ZFS knows how to avoid getting in trouble in such cases.

Mostly I think we need better documentation for the sorts of things experienced admins expect to be able to do.  I'd love to see a clear statement of what the gui installer does.  So far as I know, the text installer script is as close to a statement of how to install as there is.  It's not easy to follow though.

Have Fun!
Reg