Am Montag, 19. Dezember 2005 06:40 schrieb [EMAIL PROTECTED]: > Wilhelm Meier: > > The top layer unionfs would then lookup whiteouts with prefix > > .wh.<fsid1>. and the lower layer would use whiteouts with prefix > > .wh.<fsid2>., but would not block the lookup or creation with a prefix > > .wh.<fsid1>. > > So the whiteouts for each layer of all the unionfs in the stack are > > seperated. I hope it was clearer now. > > I see. > It must be useful to you. It is a good idea. I think it should be called > whiteout prefix option, in stead of fsid option. > > But it needs to be very careful to use it. > For example, > - on nfs server, /unionfs = /rw + /ro and export it as writable. > fsid=<server> - on nfs client, mount it as writable and make unionfs. > fsid=<clientA> - on nfs client, remove a 'file', which create > server:/rw/.wh.clientA.file - on another nfs client, mount it as writable > too. fsid=<clientB> > - on clientB, you can see '.wh.clientA.file' and 'file'. Removing > .wh.clientA.file, unionfs creates server:/rw/.wh.clientB..wh.clientA.file > - on clientA, you can see both of the original 'file' and '.wh.clientB...'
Yes, that is a drawback. But on the other side, clientA and clientB represent the same layer in the stack of all unionfs in this scenario, and therefore all id's should be the same. Well, I think we should call this option layerid instead of fsid. The general problem is the problem of the layering of unionfs, with or without nfs in between (for now, unionfs forbids to use another unionfs as the fs on a branch, but with nfs ...) I would like to get some feedback on this topic from the developers too. > > Finally, fsid option will conflict a writable unionfs-ed nfs share and > general nfs semantics. And it is needed to consider/design useing with > delete=whiteout option, and the case when the client does not use fsid > option while the server use it. > It might be a unionfs general problem of 'which branch we should > process?' (I hope you have ever read my rename2.patch) > > In this case, I think it is better to use unionfs on nfs clinet only, > without fsid option. I mean stop nesting. > > > Junjiro Okajima > _______________________________________________ > unionfs mailing list > [email protected] > http://www.fsl.cs.sunysb.edu/mailman/listinfo/unionfs -- -- Wilhelm Meier email: [EMAIL PROTECTED] _______________________________________________ unionfs mailing list [email protected] http://www.fsl.cs.sunysb.edu/mailman/listinfo/unionfs
