9.1 and gmirror with GPT?

[freebsd at johnea.net]

On 2012-10-22 15:54, Warren Block wrote:
> On Mon, 22 Oct 2012, freebsd at johnea.net wrote:
> 
>> On 10/21/2012 07:32 AM, Warren Block wrote:
>>> On Sun, 21 Oct 2012, Lucas B. Cohen wrote:
>>>
>>>> On 2012.10.20 20:17, freebsd at johnea.net wrote:
>>>>> Just wondering if 9.1 will bring any improvement to the situation of creating a full disk geom mirror while also using GPT partition table?
>>>>
>>> At present, MBR partitioning is recommended with gmirror(8).
>>
>> I've been reading your article on formatting disks in FreeBSD:
>> http://www.wonkity.com/~wblock/docs/html/disksetup.html
>>
>> Do you have any docs on setting up MBR using gpart, to allign for 4K sector size drives?
> 
> This is a copy from the update of the gmirror section I'm planning to commit to the Handbook.  For a single drive, replace mirror/gm0 with just the drive name, like ada4.
> 
> # create the MBR and add a FreeBSD slice
> gpart create -s MBR mirror/gm0
> gpart add -t freebsd -a 4k mirror/gm0
> 
> # create the bsdlabel partitions in slice 1 (s1)
> gpart create -s BSD mirror/gm0s1
> gpart add -t freebsd-ufs  -a 4k -s 2g mirror/gm0s1
> gpart add -t freebsd-swap -a 4k -s 4g mirror/gm0s1
> gpart add -t freebsd-ufs  -a 4k -s 2g mirror/gm0s1
> gpart add -t freebsd-ufs  -a 4k -s 1g mirror/gm0s1
> gpart add -t freebsd-ufs  -a 4k       mirror/gm0s1
> 
> # put bootcode on the MBR and mark the first slice active
> gpart bootcode -b /boot/mbr mirror/gm0
> gpart set -a active -i 1 mirror/gm0
> 
> # put bootcode on the bsdlabel
> gpart bootcode -b /boot/boot mirror/gm0s1

That helps a lot Warren!

In recent years I've just been creating a swap partition and one big root partition. It just seems as soon as I make all the traditional partitions, one runs out of room.

Do you feel there are any major disadvantages of this approach?

To create a swap and then a root that fills the rest of the disk, must the swap be created first, like this:

gpart add -t freebsd-swap -a 4k -s 4g mirror/gm0s1
gpart add -t freebsd-ufs  -a 4k       mirror/gm0s1

Is there any other way to tell gpart to create the / partition using all space except 4G?

Thank You!

johnea