Re: [Libvir] virDomainConfigureDevice?

Hugh Brock wrote: >I'm looking at ways to replicate xm block-configure at the libvirt >level. xm block-configure is useful in that it allows you to change the >back device for an HVM guest while the guest is still running; this >permits you for example to change the CDROM without shutting down your >guest or poking around in xenstore. Thus we can have an "eject" button >on cdrom devices in virt-manager (or "eject" and "load" buttons, I >guess), which we really need. > >The issue of course is that xm block-configure is specifically intended >for block devices and takes arguments for the back device and the front >device (among others). We would naturally prefer to accept a block of >XML just as virDomainAttachDevice does and then parse it, determine if >the device in question is of a type we can actually edit, determine if >the new backdev is appropriate, and so on. Definitely this will be useful for USB ... I think the question is: Should we have another entry point (virDomainConfigureDevice), or should we just modify virDomainAttachDevice so that if it sees XML for a device which is already attached it just modifies the device?

>None of this seems terribly hard, but before I go implement it, are >there obvious pitfalls I'm not thinking? And given that >virDomainAttachDevice is not implemented for qemud in libvirt (is it?), >how do we handle the non-xen case? It seems like it isn't implemented for qemud. Changing the CD-ROM is possible through the qemu monitor, so it should be.