[indiana-discuss] rpool and zfs usage

[Richard Elling]

Michael Hunter wrote:
> On Mon, 02 Jun 2008 14:07:14 -0700
> Richard Elling <Richard.Elling at Sun.COM> wrote:
>
> [...]
>   
>>> OK, got that the first time.  I understand why it is hard at boot.  But
>>> are you saying it isn't a good idea in general or just at boot?  And if
>>> in general then why?
>>>   
>>>       
>> It isn't a good idea in general, and it is especially a bad idea
>> for boot.  Think of it this way, if you stripe disks together,
>> then you get more space, but you also divide the reliability
>> by the number of disks.  In other words, your new, striped
>> configuration will be less than half as reliable as a simpler
>> configuration.  If you can't boot, then you can't do anything,
>> so it is important that boot devices are reliable.
>>     
> [...]
>   
>> I can give you a gun and bullets, but if I could also
>> prevent you from shooting a hole in your foot, wouldn't
>> that be valuable?  Or is it more "pro-user" to allow you
>> to shoot yourself?
>>     
>
> I'm a cake and eat it guy.
>
> [...]
>   
>> You can do installations with mirrored boot devices today using
>> JumpStart.  The GUI installer folks are working on improving it,
>> also.  But raidz for boot is much farther out.  Even if your BIOS
>> supports it (methinks many won't) then the changes to grub will
>> have to be made. That will take longer, even if demand exists.
>>
>> In the bad old days when desktops had 40 MByte hard disks,
>> optimizing for space while installing the OS was a much different
>> task.  For today, when you can't purchase new storage anywhere
>> near that size, the pain of squeezing an OS onto the disks has
>> been eliminated.  Even the $269 Eee Box has an 80 GByte disk :-)
>>     
> [...]
>
> You havn't considered if there are multiple drives giving the option of
> having the rpool be some part of the disk and leaving the rest to the
> user to stripe, mirror, make multiples out of, etc.  As you said space
> is cheap I don't mind rpool being a little fat (say 2x or 3x a liberal
> estimation).  The way you've done it now if I want to use the space on
> my other drive I'm going to have 2 pools anyways.  Why not allow them
> to be used in a way that is more associated with how I administer and
> want to use them?
>   

That is a temporary limitation of the GUI installer.  You might
take a look at, and join, the caiman project
    http://opensolaris.org/os/project/caiman/
 -- richard