On Thu, Jul 22, 2010 at 06:04:31PM +0100, Andrew Gabriel wrote: > Robert Gordon wrote: > >On Jul 22, 2010, at 10:57 AM, Andrew Gabriel wrote: > > > >>Sorry, but why is this restriction necessary? > > > >The team thought that if an administrator created a zone to > >partition data with the intent to share data from that zone, > >allowing another zone to share it's root, probably didn't make > >sense. > > > >Are you saying that this is something we should not actively prohibit ? > > Let the administrator decide. All you achieve by adding arbitrary > restrictions is you will prevent someone from using Zones to solve > an issue they have, for which Zones would otherwise have been ideal, > and everyone loses. There are plenty of other reasons to use Zones > which are nothing to do with partitioning data.
At least one restriction is needed: only one of the g-z and ngz can share any of the ngz's resources. But because existing systems can only share ngz resources from the g-z you'll necessarily have to deal with what to do when an ngz tries to share a resource already shared by the g-z. The question is: how? I can see any number of options, such as: 1) Don't allow ngzs to share filesystems unless they've been marked as capable of it, which in turn will only happen if the relevant datasets have been marked as not shareable by the g-z, which in turn can only happen if they aren't shared by the g-z. Thereafter you could not share that ngz's filesystems from the g-z. 2) Don't allow ngzs to share filesystems shared by the g-z. What error will be returned to the ngz sysadmin though? 3) Don't allow the g-z to share filesystems shareable by ngzs. 4) Don't allow booting of ngzs whose datasets are shared by the g-z, and don't allow the g-z to share datasets owned by a booted zone. (1) is fully backwards compatible, but probably requires lots of extra work. (2) and (4) are only slightly backwards incompatible, and that incompatibility strikes me as tolerable. (4) probably requires significant extra work too. (3) Would be a very noticeable, incompatible change. There may be other options too. > If I understood correctly that there's some technical reason a > directory can't be shared by more than one NFS instance, then check > for just that. Don't add other unnecessary restrictions, > particularly ones which break current functionality which people may > be using. Right, that's (2) above, and it's the simplest option. Nico -- _______________________________________________ opensolaris-arc mailing list opensolaris-arc@opensolaris.org
