[OpenAFS-devel] Re: [OpenAFS] Re: 1.6 and post-1.6 OpenAFS branch management and schedule

[Andrew Deason]

On Thu, 17 Jun 2010 23:38:18 +0100
Simon Wilkinson <sxw@inf.ed.ac.uk> wrote:

> If you're a new user to OpenAFS, how on earth do you work out which
> set of settings you should be using? Do you know that you're using the
> Demand Attach Fileserver, or whether your package is build with
> Transarc paths, or what the difference between inode and namei is? At
> some point, you'll just give up in disgust.

I think it could help this a lot if we had some better way of knowing
what options you have with given binaries, too. I mean, the answer to
"is my fileserver binary namei" is typically "strings | grep", which
seems silly to me. We need a '-V' or something that prints out the
configured options information.

> I'd really like us to standardise on a _small_ (ideally one) set of
> supported configurations which we suggest for each release
[...]
> If we believe the demand attach is ready then, IMO, it shouldn't be
> hidden behind a configuration switch. If it is, I doubt it will see
> much more use than it does at present.

But can't we recommend the use of configuration switches that are not
the default? For example, even if it's recommended, DAFS is going to be
a surprise for someone who's just using the same ./configure options
they always have, and don't know about DAFS.

A third option is also not to have either be the default, and refuse to
build unless someone says --enable-demand-attach-fs or
--disable-demand-attach-fs . That sounds a bit crazy to me, but I'm just
throwing it out there.

> My current feeling is that it would be great if we could ship both
> fileservers, side by side, with different executable names - but I
> haven't looked at any of the code to see how complex this would be to
> achieve.

I haven't actually tried this... but at least from the perspective of
the end result binaries, this seems simple. (the build process will be
annoyingly longer, though, at least).

1.5 bosserver always understands the 'fs' and 'dafs' bnodes, I'm pretty
sure, regardless of whether DAFS is enabled or not. So you can have an
'fs' bnode pointing at the non-DAFS binaries, and a 'dafs' bnode
pointing at the DAFS ones. You should be able to switch between DAFS and
non-DAFS just by stopping and starting the fs and dafs bnodes.

-- 
Andrew Deason
adeason@sinenomine.net