If the system cannot be booted, for example, it may be required recovering the system booting from a CD-ROM device.
However, there are the following concerns when booting from a CD-ROM device.
An operation mistake can easily be caused since circumstances when booting with this method and when booting from a boot disk may alter the correlation between the disk and the device special file (/dev/sd[a-z]*[1-4]*).
Only partial mirrored disks can be written in since access to the device special file of a physical slice is not restrained. Therefore, the mirroring state could collapse.
For these reasons, avoid booting from a CD-ROM device unless directed in this manual.
When mounting a file system by booting from a CD-ROM device in any procedure not described in this manual from necessity, it should be mounted as read-only.
