[Users] Migration issues with ovirt 3.3

[Gianluca Cecchi]

I've done some further tests and comparisons

In this F19 based + ovirt stable repo the difference in qemu command
line between the working run once with cd enabled of this CentOS 6.4
x86_64 and the normal run that doesn't proceed is:

run once
-drive file=/rhev/data-center/mnt/f18engine.mydomain:_var_lib_exports_iso/cc790a86-72e2-4aa2-a0b6-700756c399c3/images/11111111-1111-1111-1111-111111111111/CentOS-6.4-x86_64-bin-DVD1.iso,if=none,id=drive-ide0-1-0,readonly=on,format=raw,serial=
-device ide-cd,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0,bootindex=2

run
-drive if=none,id=drive-ide0-1-0,readonly=on,format=raw,serial=
-device ide-cd,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0


A working normal run of a WinXP 32bit VM in another oVirt 3.2.3 environment is
-drive if=none,id=drive-ide0-1-0,readonly=on,format=raw,serial=
-device ide-cd,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0

so it is the same as in 3.3.

Possible problems:

- 64bit OS
I can try tomorrow to create a CentOS 6.4 32 bit and compare results

- qemu default emulated pc version

Some comparisons

a) f18 host (AIO) with oVirt 3.2.3

qemu-kvm-1.2.2-14.fc18.x86_64

[root at tekkaman polimi]# qemu-kvm -machine ?
Supported machines are:
none                 empty machine
pc                   Standard PC (alias of pc-1.2)
pc-1.2               Standard PC (default)
pc-1.1               Standard PC
pc-1.0               Standard PC
pc-0.15              Standard PC
pc-0.14              Standard PC
pc-0.13              Standard PC
pc-0.12              Standard PC
pc-0.11              Standard PC, qemu 0.11
pc-0.10              Standard PC, qemu 0.10
isapc                ISA-only PC

When I start WinXP (32bit of course) I see this command line:
/usr/bin/qemu-kvm -name winxp -S -M pc-0.14 -cpu Opteron_G3 ....

b) f19 host in oVirt 3.3

qemu-kvm-1.4.2-11.fc19.x86_64

[root at f18ovn03 ~]# qemu-kvm -machine ?
Supported machines are:
none                 empty machine
pc                   Standard PC (i440FX + PIIX, 1996) (alias of pc-i440fx-1.4)
pc-i440fx-1.4        Standard PC (i440FX + PIIX, 1996) (default)
pc-1.3               Standard PC
pc-1.2               Standard PC
pc-1.1               Standard PC
pc-1.0               Standard PC
pc-0.15              Standard PC
pc-0.14              Standard PC
pc-0.13              Standard PC
pc-0.12              Standard PC
pc-0.11              Standard PC, qemu 0.11
pc-0.10              Standard PC, qemu 0.10
isapc                ISA-only PC
q35                  Standard PC (Q35 + ICH9, 2009) (alias of pc-q35-1.4)
pc-q35-1.4           Standard PC (Q35 + ICH9, 2009)

qemu command line for a CentOS 6.4 64bit vm is:
/usr/bin/qemu-system-x86_64 -machine accel=kvm -name c6s -S -machine
pc-1.0,accel=kvm,usb=off -cpu Opteron_G2

both /usr/bin/qemu-kvm and /usr/bin/qemu-system-x86_64 are in
qemu-system-x86 rpm package.

Questions:
- given a version of oVirt, pc version in qemu generated command line
is the same for every defined VM or is there any logic depending on OS
chosen and/or bit (32 vs 64)?
- if answer to previous question is fixed pc version, is there any
particular reason to use pc-0.14 in oVirt 3.2.3 and pc-1.0 in oVirt
3.3 and not the latest available (so pc-1.2 in 3.2.3 and pc-1.3 or
pc-i440fx-1.4 in 3.3)?
- where can I find documentation about difference between the
different pc-x.y versions?
- can I use a wrapper in oVirt 3.3 to start VM with a different pc-x.y
(eg pc-0.14) and see if anything changes helping debug and solve the
problem?

Thanks,
Gianluca