Bug 1812100

Summary: [incremental_backup] backup to a network destination is not supported
Product: Red Hat Enterprise Linux Advanced Virtualization Reporter: yisun
Component: libvirtAssignee: Peter Krempa <pkrempa>
Status: CLOSED ERRATA QA Contact: yisun
Severity: medium Docs Contact:
Priority: medium    
Version: 8.2CC: jdenemar, lcheng, lmen, virt-maint, xuzhang, yisun
Target Milestone: rcKeywords: Triaged
Target Release: 8.0   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: libvirt-6.3.0-1.el8 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2020-11-17 17:47:36 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1799015    

Description yisun 2020-03-10 14:18:57 UTC 
Description of problem:
[incremental_backup] backup to a network destination is not supported 

Version-Release number of selected component (if applicable):
libvirt-6.0.0-7.module+el8.2.0+5869+c23fe68b.x86_64

How reproducible:
100%

Steps to Reproduce:
1. In rhel-av-8.2.0 libvirt branch, the docs/formatbackup.html.in mentioned the backup can be saved to a type='network' target
(or can be found at: https://libvirt.org/formatbackup.html#BackupAttributes)

root@yisun-test1 /home/libvirt-rhel 09:58:59$ git branch
* (HEAD detached at origin/rhel-av-8.2.0)

root@yisun-test1 /home/libvirt-rhel 09:55:42$ cat docs/formatbackup.html.in | grep "<dt><code>type</code></dt>" -A8
              <dt><code>type</code></dt>
              <dd>A mandatory attribute to describe the type of the
                disk, except when <code>backup='no'</code> is
                used. Valid values include <code>file</code>,
                <code>block</code>, or <code>network</code>.
                Similar to a disk declaration for a domain, the choice of type
                controls what additional sub-elements are needed to describe
                the destination (such as <code>protocol</code> for a
                network destination).</dd>

2. but in backup rng file, there is no 'network' mentioned, only 'file' and 'block' mentioned

root@yisun-test1 /home/libvirt-rhel/docs/schemas 09:51:04$ cat domainbackup.rng | grep "name='type'" -A2
        <attribute name='type'>
          <ref name='storageFormat'/>
        </attribute>
--
        <attribute name='type'>
          <value>qcow2</value>
        </attribute>
--
                <attribute name='type'>
                  <value>file</value>
                </attribute>
--
                <attribute name='type'>
                  <value>block</value>
                </attribute>
--
                  <attribute name='type'>
                    <value>file</value>
                  </attribute>
--
                <attribute name='type'>
                  <value>block</value>
                </attribute>

3. So there is no way to create a backup targeting to network block device?

Actual results:
Cannot create a backup xml with disk type='network' to carry out backup jobs

Expected result:
backup to a network storage should be supported as doc mentioned
Comment 1 Peter Krempa 2020-04-14 17:16:22 UTC 
I've removed the reference to network backups in the docs:

commit 30d2491d8b3c6c9cfef71ac0730373c5c32ac561
Author: Peter Krempa <pkrempa>
Date:   Thu Apr 9 16:19:59 2020 +0200

    docs: backup: Remove references to push backup to network disk
    
    It was never implemented and for now I don't think there's demand to do
    it. Remove the reference.
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1812100
    
    Signed-off-by: Peter Krempa <pkrempa>
    Reviewed-by: Erik Skultety <eskultet>
    Reviewed-by: Ján Tomko <jtomko>
Comment 5 yisun 2020-07-20 07:11:36 UTC 
now the doc is updated as follow:
 97               <dt><code>type</code></dt>
 98               <dd>A mandatory attribute to describe the type of the
 99                 disk, except when <code>backup='no'</code> is
100                 used. Valid values include <code>file</code>, or
101                 <code>block</code>.
102                 Similar to a disk declaration for a domain, the choice of type
103                 controls what additional sub-elements are needed to describe
104                 the destination.</dd>

And can be checked on https://libvirt.org/formatbackup.html#BackupAttributes
Since it's a doc change, won't add test case for it.
Comment 8 errata-xmlrpc 2020-11-17 17:47:36 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 (virt:8.3 bug fix and enhancement update), 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/RHBA-2020:5137