Hi Shidokht, some time ago, when discussing issue related to ZFS pools, we touched the topic of concept of alternate slice in Solaris and OpenSolaris installer - see excerpt from one of your responses [1].
At that time, OpenSolaris installer didn't create ALT slice and if one was present, it was removed. That meant that we always ended up without ALT slice present on target disk which was source of issues in some scenarios - e.g. when creating mirrored configuration of ZFS pools or installing S10 on ATA disk which was previously installed with OpenSolaris. In current version of installers (due to fix for bug 13331) if ALT slice is present on the disk (for instance as a result of creating default VTOC when Solaris2 partition is created on x86 platform), it is preserved. We would like to check with you if this is correct and appropriate behavior or if OpenSolaris installers should deal with ALT slice in different manner - e.g. if the installer should make sure that ALT slice is always created in appropriate scenarios (e.g. ATA/SATA disk handled by cmdk device driver). Also, as you indicated, the concept of alternate slice on drives handled by cmdk device driver in Solaris seems to be outdated and from longer term point of view it is something which might be removed - as it was done for SCSI or SATA drives handled by new SATA framework. Do you think that it might be reasonable to continue with that longer term effort ? Thank you very much, Jan [1] ... Yes, We don't create slice 9 for scsi disks on x86. DKIOCADDBAD ioctl has not been supported on scsi disks since PSARC 1997/281 (guess who submitted it ;-)), when we switched to use sd instead of cmdk for scsi disks. Later on, creating the alternate slice for scsi disks in sd was removed all together. I agree with this slice being kind of useless and probably nobody uses addbadsec anymore. However imho, the installer has to agree with kernel and disk partitioning utility. If we want to not make slice 9 on these devices anymore, I believe the proper way of fixing it would be by EOLing the addbadsec, DKIOCADDBAD ioctl and changing target driver, utilities and installer to all agree on that. Otherwise if addbadsec is still not ready to be EOLed, then installer should create the slice and be consistent. I think we need a low pri bug to be filed for caiman. We may need a separate RFE later probably against cmdk and format to get rid of alt slice. Perhaps it should have dealt with when sata framework was introduced and some ide devices migrated from cmdk to sd. ...
