[OmniOS-discuss] Internal pkg error during a test r151010 to r151014 upgrade

[Richard Elling]

> On Apr 7, 2015, at 8:49 AM, Chris Siebenmann <cks at cs.toronto.edu> wrote:
> 
>> Short story is that /opt is part of a namespace managed by the Solaris
>> packaging and as such is part of a BE fs tree. If you have privately
>> managed packages under certain subdirs, turn those sub-dirs into
>> separate datasets instead.
> 
> If this is the case for OmniOS, I believe that it should be strongly
> and visibly documented in the OmniOS wiki as part of the install
> instructions and so on. It is not intuitive to me at all, and in fact
> I would strongly expect that it would not be the case as /opt is where
> people have traditionally put *third party* software.

See filesystem(5)

History lesson: until people could afford to purchase more than one disk
and before Sun invented the diskless workstation (with shared /usr), everything
was under /.  Indeed, many other wildly successful OSes (MS-DOS, MS-Windows,
OSX, Android) do likewise. As such, having separate filesystems is actually 
detrimental to systems management and only arrived at the marketplace when the
OS outgrew the drives available at the time *and* people could start to afford
buying more than one drive. RAID-0 came later.

In other words, it is a bad idea to manage many filesystems under the pretense
that there is some magical contract regarding their stability. Today, we have
more options available: pooled storage, snapshots, etc. that make managing
multiple filesystems almost as easy as managing one.
 -- richard