AHCI and ZFS: root mount error

[Oliver Brandmueller]

Hi,

On Fri, Jan 15, 2010 at 09:13:39PM +0100, Romain Garbage wrote:
> After setting ahci_load="YES" in /boot/loader.conf, I get a root mount error.
> ahci seems to attach to disk correctly (I get ada0 messages with no error)
> 
> Without ahci_load="YES", system boots fine, with ata module attaching to disk.
> 
> I have a full zfs system, set up following wiki instructions:
> http://wiki.freebsd.org/RootOnZFS/ZFSBootPartition
> (MBR scheme, ZFS in a FreeBSD slice, together with a swap partition)
> 
> I'm using a GENERIC kernel, RELENG_8 branch.
> 
> My /boot/loader.conf:
> zfs_load="YES"
> vfs.root.mountfrom="zfs:zroot"
> nvidia_load="YES"
> snd_hda_load="YES"
> tmpfs_load="YES"
> coretemp_load="YES"

Check with "zpool status" if your zpool refers to diskslices like 
"ad0s1". I use gpt have setup the ZFS mirror to refer to gptids:

  pool: silver
 state: ONLINE
 scrub: none requested
config:

        NAME                                            STATE     READ WRITE CKSUM
        silver                                          ONLINE       0     0     0
          mirror                                        ONLINE       0     0     0
            gptid/9e68d234-f306-11de-a0c4-0002b3b6e838  ONLINE       0     0     0
            gptid/a025b88c-f306-11de-a0c4-0002b3b6e838  ONLINE       0     0     0

With that kind of configuration I can switch back and forth between 
using ATA_CAM or using traditional ATA drivers. Since you're not using 
GPT I gues you can use geom labels to do more or less the same thing.

In short: use labels, nut device names. Saves headaches in many cases.


- Olli


-- 
| Oliver Brandmueller          http://sysadm.in/         ob at sysadm.in |
|                        Ich bin das Internet. Sowahr ich Gott helfe. |