Re: BSDInstall: merging to HEAD

On 01/20/11 17:21, Doug Barton wrote:
> On 01/20/2011 14:47, Nathan Whitehorn wrote:
>> On 01/20/11 16:44, Doug Barton wrote:
>>> On 01/20/2011 14:15, Chuck Swiger wrote:
>>>> On Jan 20, 2011, at 1:37 PM, David Demelier wrote:
>>>> [ ... ]
>>>>> Why does the installer use GPT partition by default? Do you know
>>>>> that GPT is not supported on every (even modern) computer ?
>>>>
>>>> Sure. Legacy PC/BIOS platforms can work with a hybrid GPT which
>>>> includes the legacy or "protective" MBR used by pre-EFI systems;
>>>> FreeBSD 7 and later, recent Linux, MacOS X 10.4 and later should be
>>>> able to boot from disks with that hybrid format.
>>>>
>>>> If you need to dual-boot into Windows, however, and your hardware
>>>> doesn't provide EFI then you're likely stuck using MBR + PC/BIOS only.
>>>
>>> We should not do anything by default that damages the ability to
>>> dual-boot windows (and by windows I really mean "xp or later" since
>>> we'll have xp around through 2014). If there are significant
>>> advantages to gpt as a default when possible then it will be necessary
>>> to ask the user some intelligent questions such as "Will this system
>>> be multi-booted?" and if yes, "Will
>>> ${lowest_common_denominator:-windows} be installed?"
>>
>> It does do exactly what you suggest. It only uses GPT by default if you
>> have a totally unformatted disk or indicate you intend to run only
>> FreeBSD on the machine. Otherwise, you get MBR+bsdlabel just like now.
>
> That isn't exactly what I suggested. :)  Imagine the following 
> scenario (which is what I used to do, until our fdisk started using 
> wacky geometries):
> 1. Get new computer and/or new hard drive
> 2. Boot freebsd from installation/live media (aka, disc1)
> 3. Unceremoniously (and in some cases gleefully) delete all existing 
> partition/slices
> 4. Slice the disk, and write out the changes with "regular" MBR
> 5. Boot windows, install into the first unused slice/partition
>
> Now if by "indicate you intend to run only FreeBSD on the machine" 
> above you mean that you already have questions built into the process 
> that covers what I proposed above, then fine. My point is simply that 
> running the installer on a blank (or newly blank'ed) disk is not by 
> itself a sign that everything that will be installed understands gpt.
It does. It only does GPT by default if you say "I want to erase my hard 
disk" (or it is already blank), then select "Automatic partitioning". If 
you have an existing partition scheme, it is kept even if you select 
"automatic" (assuming it is bootable on your platform).

If you want something more complicated (i.e. any kind of dual-booting 
scenario), then you will want to specify partition sizes with the editor 
anyway. Once you exit automatic mode to invoke the editor, it allows you 
to set up bsdlabel-only, MBR+bsdlabel, GPT, installations spanning 
multiple disks, and whatever else you might want to do. If that isn't 
enough flexibility, there is also a "I don't need no stinking partition 
editor" option, where you can set up whatever you like with a shell.
-Nathan