Liane Praza writes: > James Carlson wrote: > > Liane Praza writes: > >> [1] I have a concern about a 'run-last' mechanism, given that there were > >> two posited consumers for it within 24 hours of it being proposed, which > >> is the same thing that happens every time such a mechanism is proposed. > > > > Really? I saw exactly one consumer -- the UPS shutdown case. I must > > have missed the other. > > Jordan's patching consumer, right?
He doesn't want that one to go last at all; it can't. > > The semantics I was expecting was that all of the services with this > > flag would go into maintenance (and wouldn't work at all) if there > > were more than one installed on the system. It would intentionally > > work with at most one such service. > > > > Alternatively, I suppose a special guaranteed-to-be-last FMRI could be > > reserved ... and then only one user could possibly install that way. > > Yes, that'd resolve that concern. But, what's an admin to do when they > have installed two services with the run-last expectation? EYOUCANNOTDOTHAT There'd be no such thing by design. It's not just a bit of conflicting software, but an impossible design constraint: it's not logically possible for multiple bits of serialized software to all go last. Only one can possibly make such a claim, and the guy who is going to cut off the life-giving power to the system has a pretty powerful[1] claim to that post. > I admit I haven't spent a lot of time this week thinking about which > alternative amongst those proposed in this thread is most > architecturally sound. None of them are great. :-/ > > In any event, I don't think the :true thing would work. That just > > means it has no dependencies. It doesn't necessarily guarantee that > > the service goes last on shutdown. > > Eh? As I suggested, network/loopback would depend on it. Given a > reverse-dependency-order shutdown, what's your concern? Some other service could possibly try to run after it, delaying the system power-off sequence, and allowing the UPS to cut power before we're really finished. 1. Sorry for the pun. ;-} -- James Carlson, Solaris Networking <james.d.carlson at sun.com> Sun Microsystems / 35 Network Drive 71.232W Vox +1 781 442 2084 MS UBUR02-212 / Burlington MA 01803-2757 42.496N Fax +1 781 442 1677
