I need some swap partion help on new 10.1 install

[Warren Block]

On Tue, 6 Jan 2015, Bob Willcox wrote:

> On Tue, Jan 06, 2015 at 09:11:19AM -0700, Warren Block wrote:
>> On Tue, 6 Jan 2015, Bob Willcox wrote:
>>
>>> So, what should I put in /boot/loader.conf? Can I enable both GPT and GPT IDs
>>> with this:
>>>
>>> kern.geom.label.gpt.enable="1"
>>> kern.geom.label.gptid.enable="1"
>>>
>>> And if I do, should I expect any problems with doing that?
>>
>> Both are enabled by default.  Disabling GPTID can remove some confusion,
>> but is not required.
>>
>> Make certain the swap partition has a GPT label.  'gpart show -l' shows
>> them.  If it does not have one, set one with gpart modify.
>>
>> Then use that label in fstab, in the form of /dev/gpt/labelname.
>
> Well, here's what I have on the system currently:
>
> bob at maul:7 /home/bob> sysctl -a |grep label\\.gpt
> kern.geom.label.gpt.enable: 1
> kern.geom.label.gptid.enable: 0
>
> bob at maul:7 /home/bob> gpart show -l
> =>       34  488397101  diskid/DISK-S21NNSAFC51114F  GPT  (233G)
>         34       1024                            1  gptboot0  (512K)
>       1058   16777216                            2  swap0  (8.0G)
>   16778274  471618861                            3  zfs0  (225G)
>
> So is this to be expected? Is it the gptid setting that creates the /dev/ada0
> entries?

No.  /dev/ada0 is the normal one.

Note that GEOM withering means the ada0 entry is hidden if the 
partitions are mounted or in use.  So to really see it, boot into single 
user mode.  Here, the first entry is hidden because all those partitions 
are mounted.  (So why isn't the second view hidden also, because it 
points to the same things?  I don't know.  It seems inconsistent to me, 
but I have been assured it is not.)

I don't know why the GPT labels are not shown here, even as (null). 
Maybe you have a custom kernel or some other change that disables them?

> I have another system here that has a UFS root disk and another disk that's a
> ZFS disk. It is also a recent 10.1 install and it's output looks like this:
>
> bob at tavion:5 /home/bob> gpart show -l
> =>       34  976773101  ada0  GPT  (466G)
>         34          6        - free -  (3.0K)
>         40   16777216     1  (null)  (8.0G)
>   16777256  959995872     2  (null)  (458G)
>  976773128          7        - free -  (3.5K)

This is normal, with (null) showing there are no GPT labels assigned to 
those partitions.

> =>       1  31266815  da0  MBR  (15G)
>         1        31       - free -  (16K)
>        32  31266784    1  (null)  (15G)
>
> =>       1  31266815  diskid/DISK-4C530011940607120335  MBR  (15G)
>         1        31                                    - free -  (16K)
>        32  31266784                                 1  (null)  (15G)

Notice how these are two views of the same disk.