Re: [Libvir] Concepts in storage management

Daniel P. Berrange wrote: >On Tue, Oct 16, 2007 at 04:34:26PM +0100, Richard W.M. Jones wrote: >>Daniel P. Berrange wrote: >>>http://www.redhat.com/archives/libvir-list/2007-September/msg00119.html >>Since that thread is split across two months, can I bring to everyone's >>attention the post I made yesterday: >> >>http://www.redhat.com/archives/libvir-list/2007-October/msg00057.html >> >>In particular the concept at the end that we shouldn't even try to >>support every possible remote storage, but instead allow the >>administrator to write "scriptlets" (small shell scripts with a >>well-defined input & output) to perform a set of operations: > >This is really just an implementation detail. We still need to define the >storage concepts we want to expose in the public API, before figuring out >on the backend implementation. Most of the implementation wiill pretty >much have to follow the scheme of just invoking command line tools like >lvcreate >and lvs, since formal APIs are scarse. Well, a basic set of operations would be whatever we need to implement virt-install/virt-manager remotely now, plus other suggestions as they come along. From a fairly brief scan of the virt-install & virt-manager code that would be: - Create an empty a file with given name & size & sparseness. - Detect if a named device or file exists (basically a remote stat). - Copy image to remote temporary file (for kernel/CD-ROM). - Check free space (remote statvfs). It might be nice to list LVs, but it doesn't seem to be necessary to implement remote virt-* at the moment (AFAICS).