It would be great if there's some kind of document in the wiki on this proposal.
Regards, Amit *CloudByte Inc.* <http://www.cloudbyte.com/> On Fri, Jun 6, 2014 at 9:52 PM, Tim Mackey <tmac...@gmail.com> wrote: > If you can give me the commit ID for your HEAD, I'll check and see > what's up. It could be another conflict needing resolution. > > -tim > > On Fri, Jun 6, 2014 at 12:16 PM, sebgoa <run...@gmail.com> wrote: > > > > On Jun 6, 2014, at 5:17 PM, Tim Mackey <tmac...@gmail.com> wrote: > > > >> Dave, > >> > >> I've submitted a merge review request > >> (https://reviews.apache.org/r/22270/) yesterday. > > > > Unfortunately that patch did not seem to apply cleanly. I have not dug > deep though.. > > > >> If you want to avoid > >> having to potentially deal with a bunch of conflicts, you might want > >> to see if your patches apply cleanly there and let me know. Happy to > >> help with any conflict resolution. > >> > >> btw, I didn't see a design document up on the > >> wiki( > https://cwiki.apache.org/confluence/display/CLOUDSTACK/4.5+Design+Documents > ). > >> Can you get one there and start a DISCUSS thread? It'll probably > >> tease out some gotchas you might not be aware of. > >> > >> -tim > >> > >> On Fri, Jun 6, 2014 at 11:04 AM, Dave Scott <dave.sc...@citrix.com> > wrote: > >>> Hi, > >>> > >>> Here’s a quick status update: > >>> > >>> On 16 May 2014, at 15:22, Dave Scott <dave.sc...@citrix.com> wrote: > >>> > >>>> Hi, > >>>> > >>>> On 14 May 2014, at 09:53, sebgoa <run...@gmail.com> wrote: > >>>> > >>>>> > >>>>> On Apr 9, 2014, at 2:37 PM, Dave Scott <dave.sc...@citrix.com> > wrote: > >>>>> > >>>>>> Hi, > >>>>>> > >>>>>> Following up from Tim's "Support pure Xen as a hypervisor" proposal > last month[1] I'd like to start working on this and maybe even make a > little bit of progress while I'm at CCC in Denver. > >>>>>> > >>>>>> Helpfully James Bulpin managed to get CS + libvirt + xen to start > an instance in a simple configuration. Although the patches[2] are not > intended to be production-ready :) they help highlight some of the areas we > need to change. > >>>>> > >>>>> Dave, just to let you know that Tim has done some important > "refactoring" to split up XenServer hypervisor in CS between Xen and > XenServer. That way we could keep using xapi for XS but start moving to > libvirt for Xen. > >>>>> > >>>>> Tim worked in the xen2server branch (don't ask about the name, I > messed it up…:) ). > >>>>> > >>>>> > https://git-wip-us.apache.org/repos/asf?p=cloudstack.git;a=shortlog;h=refs/heads/xen2server > >>>>> > >>>>> Would be nice to see some of the libvirt stuff in that branch to > handle a new driver for Xen. > >>>>> > >>>>> Since the two hypervisors will be split up, we could still drop in > some early libvirt patches to handle Xen and put this in 4.5 as a wip. > >>>> > >>>> Thanks for the links. > >>>> > >>>> I’m slowly building up a set of patches here: > >>>> > >>>> https://github.com/djs55/cloudstack/tree/virsh-capabilities > >>>> > >>>> I think once I’ve gotten to a stable-ish point I’ll rebase on top of > Tim’s branch. > >>>> > >>>> So far I’ve > >>>> * changed the hypervisor detection to use ‘virsh capabilities’ in one > place and ‘cat /sys/hypervisor/type’ in another. Thinking about it again, I > think it’s probably best to standardise on /sys/hypervisor/type since that > will succeed irrespective of whether the libvirtd service is chkconfig’d on > or not. > >>>> > >>>> * in the python cloudutils system setup stuff isKvmEnabled() has > become isHypervisorEnabled() > >>>> > >>>> * added a XenLibvirtDiscoverer similar to the LXC one > >>>> > >>>> * fixed what I believe is a race in sshExecuteCmdOneShotWithExitCode > (which seems to hit me every time, I don’t know why other people seem to be > immune from it): see CLOUDSTACK-6621 and review board request 21261 > >>>> > >>>> * added the new hypervisor to hypervisor.list and > system.vm.default.hypervisor, so it appears in the UI properly > >>>> > >>>> * registered a system VM template in the database, using the same > qcow2 image as KVM > >>>> > >>>> For my test host I’m using a XenServer nightly snapshot which comes > with a nice modern xen and kernel, and is easy to install bleeding-edge > libvirt on top. I had to tweak the kernel configuration and the network > configuration but I’m hoping to make it work out of the box in future. > >>>> > >>>> When I deploy my ‘datacenter’ the discovery phase works, the agent > connects and looks healthy in the logs and the UI. The next step is to > figure out why the system VM template isn’t being copied to primary storage > — for some reason the copy isn’t being attempted but I can’t see any > obvious reason why. > >>> > >>> I’m now at the stage of getting my system VMs to start via libvirt. > The main missing feature is support for <channels>: low-bandwidth private > host<->guest control channels. These channels are generally useful things > and are needed by other projects (like oVirt), so I’d like to add them to > libxl and libvirt’s libxl driver. There’s a thread on xen-devel and > libvir-devel if anyone’s interested: > >>> > >>> http://www.redhat.com/archives/libvir-list/2014-June/msg00180.html > >>> > >>> Once the <channels> are sorted, basic VM operations should work. The > next step would be to rebase my patches on top of Tim’s renaming changes > and tidy them up for review. > >>> > >>> Cheers, > >>> Dave > >>> > >>>> > >>>> Cheers, > >>>> Dave > >>>> > >>>>> > >>>>> -Sebastien > >>>>> > >>>>>> > >>>>>> Some of the areas are: > >>>>>> > >>>>>> 1. hypervisor detection > >>>>>> > >>>>>> Where we currently look for KVM specifically ("lsmod | grep kvm") > we could switch to either detecting any Linux hypervisor (by reading > /sys/hypervisor/type) and assuming if a hypervisor is present then we can > use libvirt on it (is this a fair assumption?) Or we could white-list “kvm” > or “xen”. Or we could query libvirt directly (perhaps via 'virsh > capabilities'?) > >>>>>> > >>>>>> 2. fiddling with the domain.xml > >>>>>> > >>>>>> When starting a domain via libvirt the XML configuration has > hypervisor-specific stuff in it. Some of this is easy to change like: > >>>>>> > >>>>>> <domain type='kvm'> > >>>>>> > >>>>>> obviously becomes > >>>>>> > >>>>>> <domain type='xen'> > >>>>>> > >>>>>> and > >>>>>> > >>>>>> <emulator>/usr/libexec/qemu-kvm</emulator> > >>>>>> > >>>>>> should probably be > >>>>>> > >>>>>> <emulator>/some/other/path/qemu-dm</emulator> > >>>>>> > >>>>>> Some is a bit more invasive (to the VM) such as the virtual > hardware type should be switched from "virtio" to "xen" (and the block > device in Linux will change from /dev/vd* to /dev/xvd*) and we'll have to > either implement or work around the lack of > >>>>>> > >>>>>> <channel type='unix'> ... > >>>>>> > >>>>>> -- I presume this is a control channel into the system VM. Perhaps > we could implement this in libvirt/libxl using vchan? > >>>>>> > >>>>>> 3. system VMs? > >>>>>> > >>>>>> It would be very convenient if the system VM images could work on > both xen and KVM. This is probably doable as long as we don't bake in > virtual hardware specific information (such as /dev/vda) in the image. We > could use the qcow2 format in both cases. What do you think? > >>>>>> > >>>>>> … and I’m sure there’s more. > >>>>>> > >>>>>> Anyway, feedback would be welcome. If anyone else in Denver wants > to chat, then come grab me later! > >>>>>> > >>>>>> Cheers, > >>>>>> Dave Scott > >>>>>> > >>>>>> [1] > http://mail-archives.apache.org/mod_mbox/cloudstack-users/201403.mbox/%3ccajgxtbnbmqtq81ralgh2kma7v5wjyzkr3xnyasmkc_br+uk...@mail.gmail.com%3e > >>>>>> > >>>>>> [2] > https://github.com/jamesbulpin/cloudstack/commits/jamesb_xen_exploratory > >>> > > >
