Just a quick correction and apologies, the actual issue is that http  will not work, https will so I dont think this is a bug as such I think this is by design likely for security.


Looking at the man page for qemu-kvm it states http will work with examples given however only https works, my best guess from looking at the spec file from the srpm is that it has only been enabled in the centos qemu-kvm-ev with https:


except from spec file: 

- Resolves: bz#1132569
  (RFE: Enable curl driver in qemu-kvm-rhev: https only)

example working XML except:


<disk type='network' device='cdrom'>
    <driver name='qemu' type='raw'/>
    <source protocol="https" name="/debian-cd/current/amd64/iso-cd/debian-9.5.0-amd64-netinst.iso">
      <host name="mirror.bytemark.co.uk" port="443"/>
    </source>
    <target dev='hdb' bus='ide' tray='closed'/>
    <readonly/>

I have tested this on a base install with the regular packages and can confirm that it works fine over https.


Thanks again and sorry for any confusion caused.


From: Daniel P. Berrangé <berrange@redhat.com>
Sent: 09 August 2018 11:29:25
To: Inception Hosting
Cc: Vasiliy Tolstov; libvirt-users@redhat.com
Subject: Re: [libvirt-users] Mount URL as cdrom/iso KVM/QEMU
 
On Thu, Aug 09, 2018 at 10:20:54AM +0000, Inception Hosting wrote:
> Resolved this morning,
>
>
> the issue is that the qemu-kvm-ev rpm's released by centos have not
> been compiled with curl support, I rebuild it myself from source with
> curl support and it works fine now.

Hmm that's bad, because if curl was disabled, we really want to have
QEMU refuse to startup, rather than start & give you an inaccessible
file. So this feels like a QEMU bug to me that ought to be reported.


Regards,
Daniel
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