Re: Disk and partition sizes (Was: sun4c)

[David Brownlee <abs%netbsd.org@localhost>]

On 27 June 2012 11:27, Julian Coleman <jdc%coris.org.uk@localhost> wrote:
> Hi,
>
>> Oh? thats been fixed? Brilliant. Back in the not-so-recent-unpleasantness
>> 2.0 or below(?) era I had a 4gb disk sliced up into roughly 900mb slices +
>> swap and misc. Worked fine. I then became overly zealous and fed it a 18gb
>> disk off two levels of converters and went gangbusters up to the point
>> where some counter wrapped and the fs was corrupted.
>
> I'm not sure that this problem has been fixed.  The two different problems
> are: 1) the firmware being only able to access the first chunk of disk (see
> sparc/boot(8) for limitations), and; 2) corruption using larger disks in
> some machines.
>
> For the first problem, there is no fix, so it's simplest to make the boot
> partition no larger than the requisite size (or 1GB to work on multiple
> machines).

The sparc boot(8) mentions:

     On sun4 machines, the NetBSD sparc boot loader can only boot from RAID
     partitions that start at the beginning of the disk.

     On sun4 and early PROM version sun4c machines, the PROM can only boot
     from the first 1Gb of the disk.

     On later PROM version sun4c and early PROM version sun4m machines, the
     PROM can only boot from the first 2Gb of the disk.

     On later PROM version sun4m machines, the PROM can only boot from the
     first 4Gb of the disk.

Does anyone have any updates on that?  :)

> I'm guessing too that the second problem is also a hardware limitation with
> the ESP 100A (NCR53C90 clone) used in the SS2(*), where the SS20 uses an
>  ESP 200, and there have been reports of 18GB disks in SS20's.  However, I'm
> not sure if there also limitations there as well.

Presumably the test case in both situation is to create a filesystem
which starts past a certain limit and then try to boot from/use it?

Does anyone have a >8GB disk and a selection of machines spare for
which they are willing to create a filesystem which starts >8GB and
test mounting and writing to it? It would be nice to confirm if this
is still an issue, and if so on what hardware...