kern/143056: atacontrol can not create raid1 (mirror) from one drive
don_oles at able.com.ua
Thu Jan 21 15:00:19 UTC 2010
>Synopsis: atacontrol can not create raid1 (mirror) from one drive
>Arrival-Date: Thu Jan 21 15:00:18 UTC 2010
>Originator: Oles Hnatkevych
>Release: FreeBSD 6.4
atacontrol create raid1 ad4
This command fails with the message
atacontrol: At least 2 disks must be specified
This is bizarre since there MUST be a possibility to create 'degraded' mirrors for the purpose of attaching a second drive after the one-drive-mirror is created, as part of provisioning.
If the check is commented in atacontrol.c then it fails with the ioctl error, so the limitation is in the kernel driver.
More information about the freebsd-bugs