Question has been answered. Thanks.
On Thu, May 25, 2017 at 6:35 PM, Bruno Alvisio <bruno.alvi...@gmail.com>
wrote:
> Hello all,
>
> Summary
>
> I am using XEN hypervisor to run a HVM with a QEMU backed disk. After I
> start the HVM I use QMP "query-block" command to see the devices of the VM.
> Initially the command returns the disk that I set as part of the
> configuration but after a few seconds the "query-block" command returns an
> empty result.
>
> KVM Version: 4.6.5
> Arch: x86-64
> QEMU : 2.2.1
>
>
> I was expecting to see the device information in QEMU such as:
>
> {"execute":"query-block"}
>
> {"return": [{"io-status": "ok", "device": "ide0-hd0", "locked": false,
> "removable": false, "inserted": {"iops_rd": 0, "detect_zeroes": "off",
> "image": {"virtual-size": 10737418240, "filename": "/home/balvisio/
> debian-disk.img", "format": "raw", "actual-size": 4940075008,
> "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0,
> "drv": "raw", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0,
> "bps_rd": 0, "file": "/home/balvisio/debian-disk.img",
> "encryption_key_missing": false}, "type": "unknown"}]}
>
>
>
> I wanted to understand how the storage subsystem work for QEMU backed
> disks. Any help and pointers in the code would be great.
>
> Eventually I would like to implement a feature in XEN to allow migration
> of instances with local disks.
>
> Thanks,
>
> Bruno
>
>
> DETAILED LOGS
>
> I am using XEN hypervisor to run a HVM with QEMU backed disk. When I start
> the HVM I see the following QEMU process started:
>
> root 2199 1 0 18:57 ? 00:00:02
> /usr/local/lib/xen/bin/qemu-system-i386 -xen-domid 3 -chardev
> socket,id=libxl-cmd,path=/var/run/xen/qmp-libxl-3,server,nowait
> -no-shutdown -mon chardev=libxl-cmd,mode=control -chardev
> socket,id=libxenstat-cmd,path=/var/run/xen/qmp-libxenstat-3,server,nowait
> -mon chardev=libxenstat-cmd,mode=control -nodefaults -no-user-config
> -name debianL2 -vnc :0,to=99 -display none -serial pty -device
> cirrus-vga,vgamem_mb=8 -boot order=d -device
> rtl8139,id=nic0,netdev=net0,mac=00:16:3e:1b:d0:7e
> -netdev type=tap,id=net0,ifname=vif3.0-emu,script=no,downscript=no
> -machine xenfv -m 1016 -drive file=/home/balvisio/debian-dis
> k.img,if=ide,index=0,media=disk,format=raw,cache=writeback -drive
> if=ide,index=2,readonly=on,media=cdrom,id=ide-5632,file=/hom
> e/balvisio/debian-live-8.7.1-amd64-gnome-desktop.iso,format=raw
>
> After launching the VM, I connected to the QMP socket:
>
> # rlwrap -C qmp socat STDIO UNIX:/var/run/xen/qmp-libxl-2
>
> {"QMP": {"version": {"qemu": {"micro": 1, "minor": 2, "major": 2},
> "package": ""}, "capabilities": []}}
>
> {"execute":"qmp_capabilities"}
>
> {"return": {}}
>
> I issue the "query-block" command and I get
>
> {"execute":"query-block"}
>
> {"return": []}
>
>
> Xen Config File Used
>
> kernel="/usr/local/lib/xen/boot/hvmloader"
>
> builder='hvm'
>
> memory=1024
>
> vcpus=1
>
> name="debianL2"
>
> vfb = ['type=vnc']
>
> vif= ['bridge=xenbr0']
>
> boot='b'
>
> disk=['file:/home/balvisio/debian-disk.img,xvda,w']
>
> acpi=1
>
> device_model_version='qemu-xen'
>
> serial='pty'
>
> vnc=1
>
> vnclisten=""
> vncpasswd=""
>
>
>
>
>
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
