On Fri, 13.02.15 09:49, Andrei Borzenkov ([email protected]) wrote: > В Wed, 11 Feb 2015 21:19:16 +0100 > Lennart Poettering <[email protected]> пишет: > > > > > > > But the problem is not limited to legacy initscripts. It makes it > > > generally unsafe to have aliases via symlinks. Aliases were always > > > meant "for compatibility" but this problems exactly means that > > > "compatibility" is broken here - when you replace unit A with > > > compatibility link to unit B things may be broken unless you always > > > refer to A when you refer to B. At which point why have alias at all? > > > > I think it's completely Ok that dependencies on aliases only work as > > long as they are referenced at least once by them. This isn't really > > that surprising a behaviour I think. > > > > Sorry if I was not clear. User had WantedBy=A.target in the past and > other places had Want/Require=A.target. Now A.target -> B.target and > all other places were adjusted to Want/Require=B.target. As was > demonstrated all user units that were using WantedBy=A.target are now > effectively broken. > > Aliases imply that they are interchangeable. If they are not that must > be at least quite clear and explicitly stated so in manual. If aliases > are not interchangeable than the only use case I can see is for one way > migration from old to new name but exactly this use case is broken.
Sure, we can always have more documentation. But I think they actually have a lot of uses still, since they allow mapping of some fixed name to a variety of different choices. As long as the fixed name is explicitly requested all is good. Lennart -- Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/systemd-devel
