Re: (ITS#6531) Modify updateref to generate referrals on the backend

[masarati@aero.polimi.it]

[snip]

>> Although redesigning referral generation in slapd could streamline
>> things,
>> I don't quite see what issues can't be addressed using a global instance
>> of slapo-chain.  You can configure referral chasing differently for
>> different domains using the chain-uri directive.  I favor fixing only
>> what's actually broken.
>
> The request revolves around having different behavior for different
> databases.
> With a global slapo-chain you cannot turn off referral chasing; URIs that
> are
> not explicitly configured will still be chased.
>
> Also in terms of logical abstraction the current behavior is wrong; the
> frontend should of course generate the default_referral responses but
> updateref is a per-backend item and should be generated at the backend
> layer.
> Ideally this would all have been fixed to behave correctly by moving all
> replication support into an overlay, where it properly belongs. As an
> interim
> step it would be trivial to write an updateref overlay that supersedes the
> current updateref behavior.

As I said, I recognize the usefulness of such a change: I first moved
replication into an overlay (ITS#4261).  I'm questioning its need for the
case at hand.  Perhaps allowing slapo-chain to ignore some URIs would be
easier to implement, and generally useful in other applications.

In any case, I might spare some time to revitalize (ITS#4261), now that
slurpd is no longer around and thus things simplify significantly.

p.