Adding a swap partition to the March 5 snapshot image

[bob prohaska]

On Thu, Mar 05, 2020 at 09:26:42PM -0800, Mark Millard wrote:
> 
> On 2020-Mar-5, at 20:54, bob prohaska <fbsd at www.zefox.net> wrote:
> > 
> > I've been trying for a while to set up an armv7 RPI2 with a single
> > root partition plus a swap partition at the end of mmcsd0. Letting
> > firstboot invoke growfs seems not to help, since growfs leaves no
> > space for swap.
> > 
> > Attempts using gpart in single-user give the appearance of 
> > working, but on reboot the machine stops at the mountroot prompt.
> > This method worked well in July of 2018. Seemingly, no more. 
> > 
> > Has something changed? 
> > 
> > Mounting the armv7 card on a second Freebsd box and making the changes 
> > appears to work also, but on the initial boot (firstboot disabled) the 
> > machine stops at the mountroot prompt on initial boot.
> > 
> > If there's a better way to pursue the same end I'd be grateful for
> > a hint. Perhaps giving a swap size  parameter to firstboot? 
> 
> You have not reported what shows if you enter a "?" command at the
> mountroot prompt. (As I remember that lists what mount root
> classifies as available.)
> 
> That might prove to be useful information.
> 

Indeed so. I've put a near transcript of a session at
http://www.zefox.net/~fbsd/rpi2/rpi2_swap_installation

The punchline seems to be that in the course of resizing
mmcsd0s2a and adding mmcsd0s2b the /dev/ufs/ device
went away. Manually entering ufs:/dev/mmcsd0s2a allows
a one-time mount and boot to multi-user.

I certainly didn't intentionally delete any files, the only
change (apart from the rather drastic measures taken with
gpart) was to rename /firstboot to /no.firstboot.

The only hint of possible mischief is:
# gpart resize -i 2 mmcsd0
GEOM_PART: mmcsd0s2 was automatically resized.
  Use `gpart commit mmcsd0s2` to save changes or `gpart undo mmcsd0s2` to revert them.
mmcsd0s2 reized
         ^^^^^^
[Note the misspelled message. I do not recall the prompt to commit from 2018]
[The gpart man page implies commit is automatic, except using special options]


Hopefully sharper wits than mine trained on the transcript will find the error.
Some of the comments in growfs imply it takes a size parameter. That would help,
but I couldn't recognize how to do it. 

Thanks for reading,

bob prohaska