Bug 1400205 - Add --vdsm-compat=1.1 flag for VDSM
Summary: Add --vdsm-compat=1.1 flag for VDSM
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: libguestfs
Version: 7.4
Hardware: Unspecified
OS: Unspecified
Target Milestone: rc
: 7.4
Assignee: Richard W.M. Jones
QA Contact: Virtualization Bugs
Yehuda Zimmerman
Whiteboard: V2V
Depends On: 1359086
Blocks: 1395265 1401400 1406854 1412451
TreeView+ depends on / blocked
Reported: 2016-11-30 17:00 UTC by Richard W.M. Jones
Modified: 2017-08-01 22:11 UTC (History)
13 users (show)

Fixed In Version: libguestfs-1.36.1-1.el7
Doc Type: Release Note
Doc Text:
*virt-v2v* can export disk images to qcow2 format 1.1 With this update, the *virt-v2v* utility exports disk images compatible with qcow2 format version 1.1 when using the "-o rhev" option. In addition, *virt-v2v* adds the "--vdsm-compat=COMPAT" option for the vdsm output mode. This option specifies which version of the qcow2 format *virt-v2v* uses when exporting images with the "-o vdsm" option.
Clone Of:
: 1406854 (view as bug list)
Last Closed: 2017-08-01 22:11:26 UTC
Target Upstream Version:

Attachments (Terms of Use)

System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2017:2023 0 normal SHIPPED_LIVE libguestfs bug fix and enhancement update 2017-08-01 19:32:01 UTC

Description Richard W.M. Jones 2016-11-30 17:00:58 UTC
Description of problem:

Support for RHEV with RHEL 6 nodes required us to output the old style
qcow2 compat=0.10 images.  Since RHEV 3.6 GA, RHEL 6 has not been
supported as a RHEV node type.

There are significant downsides to using qcow2 compat=0.10 instead of
the modern default (compat=1.1), so stop forcing compat=0.10 for these

Patch sent upstream:

This bug is for tracking inclusion of this change in RHEL 7.4.

Version-Release number of selected component (if applicable):


Comment 1 Richard W.M. Jones 2016-12-01 13:24:13 UTC
I modified the plan a little bit in the updated patch:


There's now a new --vdsm-compat-11 flag which VDSM needs to pass
if the node is using RHV >= 4.1 & RHEL >= 7.

Eventually (not for this bug) the flag will become the default, when
RHV 4.1 minimum is present everywhere.

Comment 3 Richard W.M. Jones 2016-12-07 10:03:36 UTC
New version of this patch:


Comment 4 Pino Toscano 2016-12-21 14:46:34 UTC
Fixed with
which is in libguestfs >= 1.35.15.

Comment 12 kuwei@redhat.com 2017-03-13 05:36:52 UTC
Verify the bug with below builds:

Verify steps:
 Check the  option "--vdsm-ovf-output" details on man page.
#man virt-v2v
If -o vdsm and the output format is qcow2, then we add the qcow2
compat=0.10 option to the output file for compatibility with RHEL 6
(see https://bugzilla.redhat.com/1145582).

If --vdsm-compat=1.1 is used then modern qcow2 (compat=1.1) files
are generated instead.

Currently --vdsm-compat=0.10 is the default, but this will change
to --vdsm-compat=1.1 in a future version of virt-v2v (when we can
assume that everyone is using a modern version of qemu).

Note this option only affects -o vdsm output. All other output
modes (including -o rhev) generate modern qcow2 compat=1.1 files,

Scenario 1:
1:Prepare a geust with format "qcow compat=0.10" ,then using virt-v2v convert guest to rhv4.1 with option "-of qcow2"

# virt-v2v -i disk kvm-rhel7.1-x86_64-qcow2.img -o rhev -os -of qcow2

2.After conversion successfully,check the format:
#qemu-img info 61095968-bf03-4ad1-807b-eed855eb1737
image: 7a9cfb93-0397-40e7-87d0-89b9bb14f162
file format: qcow2
virtual size: 9.0G (9663676416 bytes)
disk size: 4.4G
cluster_size: 65536
Format specific information:
    compat: 1.1
    lazy refcounts: false
    refcount bits: 16
    corrupt: false
1:Convert a guest with format raw to rhv wiht option "-of qcow2",after conversion the format is qcow compat=1.1.
2:Convert a guest with format qcow compat=1.1 to rhv with option "-of qcow2",after conversion the format is qcow compat=1.1.

Scenarion 2:
1:Prepare a guest with format "raw" , convert it to rhv4.1 using option "--vdsm-compat=0.10",after conversion the format is qcow compat=0.10.
2:Prepare a guest with format "raw" , convert it to rhv4.1 using option "--vdsm-compat=1.1" ,after conversion the format is qcow compat=1.1

Scenario 3:
1:Prepare a guest with format "raw",then convert it to rhv4.1 without option "--vdsm-compat"
# virt-v2v  win7-raw -o vdsm --vdsm-image-uuid 12345678-1234-1234-1234-123456789011 --vdsm-vol-uuid 12345678-1234-1234-1234-123456789012 --vdsm-vm-uuid 12345678-1234-1234-1234-123456789014 --vdsm-ovf-output /mnt/165c1942-70e7-4691-aa63-9184a0569bf2/master/vms/12345678-1234-1234-1234-123456789014 -os /mnt/165c1942-70e7-4691-aa63-9184a0569bf2 -of qcow2

2:After conversion successfully ,check the format:
# qemu-img info 12345678-1234-1234-1234-123456789012
image: 12345678-1234-1234-1234-123456789012
file format: qcow2
virtual size: 12G (12884901888 bytes)
disk size: 12G
cluster_size: 65536
Format specific information:
    compat: 0.10
    refcount bits: 16
Addition info:
When using guest with fomat compat=0.10 and format compat=1.1 convert to rhv4.1  without option "--vdsm-compat" ,after conversion successfully,the format is qcow compat=0.10.

So,all the Scenario results are expects, move the bug from ON_QA to VERIFIED

Comment 15 errata-xmlrpc 2017-08-01 22:11:26 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.


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