On Fri, 17 Jan 2003, John Klos wrote:

> Let's characterise this a little more...
>
> > I've a few other slightly larger drives that in the range of
> > 4100MB-4200MB in size.  If I build their fs under 1.5.2 and later boot
> > into 1.6, the boot time fsck under 1.6 sees the filesystems as corrupt
> > and wipes out the entire thing.  If I build them under 1.6 and boot to
> > 1.5.2, the same thing happens.  If I build them on 1.6, and only boot on
> > 1.6, they seem to mostly work, until they start filling up with data.
>
> But do > 4 gig partitions work fine under 1.5.2 with any amount of data?
> If the answer is yes, we can look at all of the fs code that's changed
> between 1.5.2 and 1.6. I wish I noticed when the problem started
> happening, but there were many months around the time before and after I
> updated to 1.6 where the VAX just served web...

This is a good question.  I'm not sure about 1.5.2.  My particular
circumstances are a bit odd.  I'd just gotten my MicroVAX 3100, and the
seller had shipped a 1.5.2 CD with it.  I didn't have my ISO of 1.6
handy, so I decided to go ahead and install 1.5.2 to make sure the
system worked.  I created some large filesystems under 1.5.2, but I
didn't use them enough to see if they help up under that release.

The very next day I reinstalled the 400MB system drive with 1.6, not
touching any of the large filesystems on the other drives.  When I
rebooted into 1.6, it didn't like the >4GB filesystems at all; they
were seen as dirty.  When I let the fsck attempt to clean my >4GB
/home filesystem, it proceeded to wipe out all of it.  I was a little
puzzled; a newfs did seem to resolve the problem.

Fortunately, I didn't really have any important data on the drives yet.
Then later, when I booted into 1.5.2 in order to build a stripped down
kernel for it, I saw the same problem with 1.5.2 not being happy with
the filesystems I created under 1.6.

I'd gather that something relevant did change between 1.5.2 and 1.6,
finding changes between the two might be a good starting point, but I'm
not entirely sure that 1.5.2 is free and clear itself.

-brian.