Port-sparc archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: Re (6): installing NetBSD on a Sparcstation 2.



> Ugh...  2GB limit for the / filesystem when using anything but the
> 2.9 PROM, from what I've gathered.

For the boot filesystem, more likely.  NetBSD can work just fine with
boot and root on separate filesystems, though (at least in my
experience) you usually need a custom-configured kernel, or be willing
to type some stuff on the console at every boot.

Even then, if it's the usual problem (ROMs not knowing how to use
10-byte CDBs), the limit is 1G, not 2G (small CDBs support block
numbers from 0 to 0x1fffff).  And it's not a limit on filesystem size
per se, but rather, the limit is that every disk block read using the
ROM routines must be below the line; a large filesystem is fine if the
blocks of interest are all low down - but, with most filesystems,
that's difficult to ensure short of capping overall filesystem size.

> I have an IPC that was running NetBSD 4.something a while back, and
> I'm pretty sure it used the entire 18GB drive that was installed at
> the time.  It must have a much newer PROM, because I remember the
> NetBSD install from CD-ROM going without any problems at all.

I've seen it said that different models of Sun sometimes have different
restrictions even for apparently similar ROM revs; I've had somewhat
inconsistent results that incline me to believe it, but I've never seen
a really authoritative statement, nor have I snooped to see if the ROMs
know how to use 10-byte CDBs.

In any case, even if your IPC worked fine, it could have been sheer
luck.  I've had machines with the limit which worked fine with huge
root-&-boot filesystems for a long time, until one day a new kernel
happened to use a block over the limit - kaboom.

These days I routinely separate boot and / - or, depending on the
intended use, keep / below the limit and use it for boot too.  This
means that I don't have to care whether the machine has the limit or
not, and means that the disk can move to another machine without caring
whether the new machine has the limit either.

/~\ The ASCII                             Mouse
\ / Ribbon Campaign
 X  Against HTML                mouse%rodents-montreal.org@localhost
/ \ Email!           7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B


Home | Main Index | Thread Index | Old Index