On Fri, Aug 25, 2006 at 11:00:50PM +0100, Daniel P. Berrange wrote:
On Fri, Aug 25, 2006 at 11:55:22PM +0200, Karel Zak wrote:
On Fri, Aug 25, 2006 at 05:46:28PM +0100, Daniel P. Berrange wrote:
The current implementation of 'virsh create' takes an XML file as its only parameter & creates a domain from this. This is great if you have a suitable XML file already, but if you are just trying to automate some simple tasks from the shell then the need to use XML is a little cumbersome. Thus I was thinking perhaps we could have an alternate way to define a new VM (keep the current XML based way too of course)
QEMU for example makes it very easy to launch a new VM:
qemu -m 256 -hda /path/to/image.dsk -hdc /path/to/boot.iso
Taking inspiration from this syntax we could allow:
virsh start -m 256 -hda /path/to/image.dsk -hdc /path/to/boot.iso -name Foo
Internally, the 'start' command would simply transform these command line args into the neccessary libvirt XML and then call the normal create functions.
Another way would be have a 'genxml' command, which accepted these list of devices / config properties & then printed out appropriate XMl. This could be piped to the regular 'virsh create' command
virsh genxml -m 256 -hda /path/to/image.dsk -hdc /path/to/boot.iso \ -name Foo | virsh create -
What use better command name instead "genxml"? For example "domgen". (we have dominfo, domstate, ...).
Same odd commad name is "dumpxml"... XML of what? It should be renamed to "domdump".
Well we can't break API - and there's a whole bunch of commands which don't start with 'dom' prefix - pause, shutdown, create, resume, vcpuinfo, setmem, setmaxmem, to name just a few - apart from nodeinfo & create essentially every command performs some kinda of operation on a domain. So I think needing to prefix all with 'dom' is a little overkill.
OK. Agree.
I agree that 'genxml' is a terrible name I suggest though - domgen is nicer - or as below - just allow the args to be passed to regular create command instead of an XML file path.
I think the args for the create command is nice solution, but domgen too. We should support both. I will be very happy with something like: virsh domgen -name Foo -m 256 -hda image.dsk > /etc/xen/Foo.xml
I can imagine more commands like:
virsh> bufread /etc/xen/Foo.xml virsh> bufedit Foo -hdc /path/file.img virsh> create --frombuf Foo
I think it could be nice for playful admins and developers. Or is over engineering? ;-)
A little over-engineering - if we want to let people override contents of an XML file - i'd just combine both into one, eg
virsh create -hda /path/file.img /etc/xen/Foo.xml
Good idea. Karel -- Karel Zak <kzak@redhat.com>