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Bug 1580309 - virt-v2v rhel7.6 build can't convert guest to null with qemu-kvm rhel7.5.z build
Summary: virt-v2v rhel7.6 build can't convert guest to null with qemu-kvm rhel7.5.z build
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: libguestfs
Version: 7.6
Hardware: x86_64
OS: Unspecified
urgent
urgent
Target Milestone: rc
: ---
Assignee: Richard W.M. Jones
QA Contact: Virtualization Bugs
URL:
Whiteboard: V2V
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2018-05-21 08:47 UTC by mxie@redhat.com
Modified: 2019-08-23 10:30 UTC (History)
5 users (show)

Fixed In Version: libguestfs-1.38.2-2.el7
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
Environment:
Last Closed: 2018-10-30 07:45:35 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)
v2v_1.38.2-1-qemu-kvm_7.5.z-null.log (1.38 MB, text/plain)
2018-05-21 08:47 UTC, mxie@redhat.com 		no flags Details
View All


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHEA-2018:3021 0 None None None 2018-10-30 07:46:21 UTC

Description mxie@redhat.com 2018-05-21 08:47:57 UTC 
Created attachment 1439471 [details]
v2v_1.38.2-1-qemu-kvm_7.5.z-null.log

Description of problem:
virt-v2v rhel7.6 build can't convert guest to null with qemu-kvm rhel7.5.z build

Version-Release number of selected component (if applicable):
virt-v2v-1.38.2-1.el7.x86_64
libguestfs-1.38.2-1.el7.x86_64
libvirt-3.9.0-14.el7_5.5.x86_64
qemu-kvm-1.5.3-156.el7_5.2.x86_64


How reproducible:
100%

Steps to Reproduce:
1.Convert a guest to null by virt-v2v
# virt-v2v rhel7.5 -o null
[   0.0] Opening the source -i libvirt rhel7.5
[   0.0] Creating an overlay to protect the source from being modified
[   0.5] Initializing the target -o null
[   0.5] Opening the overlay
[   4.1] Inspecting the overlay
[ 270.4] Checking for sufficient free disk space in the guest
[ 270.4] Estimating space required on target for each disk
[ 270.4] Converting Red Hat Enterprise Linux Server 7.5 (Maipo) to run on KVM
virt-v2v: This guest has virtio drivers installed.
[ 527.5] Mapping filesystem data to avoid copying unused and blank areas
[ 530.4] Closing the overlay
[ 535.3] Checking if the guest needs BIOS or UEFI to boot
[ 535.3] Assigning disks to buses
[ 535.3] Copying disk 1/1 to qemu URI json:{ "file.driver": "null-co", "file.size": "1E" } (raw)
qemu-img: Unknown protocol 'json:{ "file.driver": "null-co", "file.size": "1E" }'

virt-v2v: error: qemu-img command failed, see earlier errors

If reporting bugs, run virt-v2v with debugging enabled and include the 
complete output:

  virt-v2v -v -x [...]



Actual results:
As above description

Expected results:
virt-v2v rhel7.6 build can convert guest to null with qemu-kvm rhel7.5.z build

Additional info:
V2V can convert guest to null with builds:
virt-v2v-1.38.2-1.el7.x86_64
libguestfs-1.38.2-1.el7.x86_64
qemu-kvm-rhev-2.10.0-21.el7_5.3.x86_64
libvirt-3.9.0-14.el7_5.5.x86_64
Comment 3 Richard W.M. Jones 2018-05-21 10:02:20 UTC 
This is horrible but I guess the only fix here is to downstream revert
commit 4699c7b6e126e07c95b67fb95df58aed87a680dd in RHEL 7 only.
Comment 4 Pino Toscano 2018-05-21 10:51:30 UTC 
(In reply to Richard W.M. Jones from comment #3)
> This is horrible but I guess the only fix here is to downstream revert
> commit 4699c7b6e126e07c95b67fb95df58aed87a680dd in RHEL 7 only.

An alternative is to detect at runtime whether qemu-img supports both JSON URLs, and the null-co driver, and only if so use the current way (i.e. revert to copying-and-discard like it was done before).

We already do something similar for OVA, see qemu_img_supports_offset_and_size.
Comment 5 Richard W.M. Jones 2018-05-21 10:59:02 UTC 
While that would certainly be nicer, it's also pretty complicated.
I wonder if we need this complexity for what is essentially a
debugging/testing feature?
Comment 6 Pino Toscano 2018-05-21 15:29:16 UTC 
Not-that-complicated (at least IMHO) approach for this:
https://www.redhat.com/archives/libguestfs/2018-May/msg00093.html
Comment 7 Pino Toscano 2018-05-22 09:07:03 UTC 
Fixed upstream with
https://github.com/libguestfs/libguestfs/commit/1b6a2b221d04e455bdd31cff09015f74487882c1
which is in libguestfs >= 1.39.6.
Comment 9 mxie@redhat.com 2018-05-24 09:39:05 UTC 
Verify the bug with below builds:
virt-v2v-1.38.2-2.el7.x86_64
libguestfs-1.38.2-2.el7.x86_64
libvirt-client-4.3.0-1.el7.x86_64
qemu-kvm-1.5.3-156.el7_5.2.x86_64
qemu-img-1.5.3-156.el7_5.2.x86_64

Steps：
1.Convert a guest to null by virt-v2v
# virt-v2v rhel7.5 -o null
[   0.0] Opening the source -i libvirt rhel7.5
[   0.1] Creating an overlay to protect the source from being modified
[   1.6] Initializing the target -o null
[   2.1] Opening the overlay
[  10.4] Inspecting the overlay
[  93.8] Checking for sufficient free disk space in the guest
[  93.8] Estimating space required on target for each disk
[  93.8] Converting Red Hat Enterprise Linux Server 7.5 (Maipo) to run on KVM
virt-v2v: This guest has virtio drivers installed.
[ 314.6] Mapping filesystem data to avoid copying unused and blank areas
[ 317.2] Closing the overlay
[ 325.7] Checking if the guest needs BIOS or UEFI to boot
[ 325.7] Assigning disks to buses
[ 325.7] Copying disk 1/1 to /var/tmp/null.SGwPbX/sda (raw)
    (100.00/100%)
[ 673.4] Creating output metadata
[ 673.4] Finishing off


Result:
   Latest Virt-v2v could convert guest to null target with qemu-kvm rhel7.5.z build,so move the bug from ON_QA to VERIFIED
Comment 11 errata-xmlrpc 2018-10-30 07:45:35 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.

https://access.redhat.com/errata/RHEA-2018:3021
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