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<p class="MsoNormal"><span style="color:#1F497D">Thanks again but how does that work when a VM is configured to have more than one disk?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">If I have a VM with a /dev/vda disk and a /dev/vdb disk, when I turn the vhostmd hook on the vm metric device gets created as /dev/vdb and the original /dev/vdb disk gets bumped to /dev/vdc.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Is that expected behavior? Will that not cause problems?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><a name="_MailEndCompose"><span style="color:#1F497D"><o:p> </o:p></span></a></p>
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<p class="MsoNormal"><b><span style="color:windowtext">From:</span></b><span style="color:windowtext"> Arsène Gschwind [mailto:arsene.gschwind@unibas.ch]
<br>
<b>Sent:</b> Tuesday, 19 April, 2016 13:06<br>
<b>To:</b> Simon Barrett <Simon.Barrett@tradingscreen.com>; users@ovirt.org<br>
<b>Subject:</b> Re: [ovirt-users] vhostmd vdsm-hook<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom:12.0pt">The metric information are available on this additional disk /dev/vdb. You may install the package vm-dump-metrics and use the command vm-dump-metrics which will display all metrics in an xml format.<br>
<br>
Arsène<span style="font-size:12.0pt"><o:p></o:p></span></p>
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<p class="MsoNormal">On 04/19/2016 10:48 AM, Simon Barrett wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span style="color:#1F497D">Thanks Arsène,</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">I have vhostmd running on the ovirt node and have set the sap_agent to true on the VM configuration. I also stopped and started the VM to ensure that the config change took effect.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">On the oVirt node I see the vhostmd running and see the following entry in the qemu-kvm output:</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">drive file=/dev/shm/vhostmd0,if=none,id=drive-virtio-disk701,readonly=on,format=raw -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x8,drive=drive-virtio-disk701,id=virtio-disk701</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">The part I wasn’t quite understanding was how this presented itself on the VM but I now see a new disk device “/dev/vdb”. If I cat the contents of /dev/vdb I now see the information that is provided from the
ovirt node, which is great news and very useful.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">Thanks for your help.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">Simon</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
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<p class="MsoNormal"><b><span style="color:windowtext">From:</span></b><span style="color:windowtext">
<a href="mailto:users-bounces@ovirt.org">users-bounces@ovirt.org</a> [<a href="mailto:users-bounces@ovirt.org">mailto:users-bounces@ovirt.org</a>]
<b>On Behalf Of </b>Arsène Gschwind<br>
<b>Sent:</b> Monday, 18 April, 2016 16:03<br>
<b>To:</b> <a href="mailto:users@ovirt.org">users@ovirt.org</a><br>
<b>Subject:</b> Re: [ovirt-users] vhostmd vdsm-hook</span><o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom:12.0pt">Hi Simon,<br>
<br>
You will need to have vhostmd running on the oVirt node and set the "sap_agent" custom property for the vm as you may see on the screenshot.<br>
<br>
<img border="0" width="664" height="125" id="_x0000_i1025" src="cid:image001.png@01D19A41.6BC269F0" alt="sap_agent"><br>
<br>
Arsène<o:p></o:p></p>
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<p class="MsoNormal">On 04/15/2016 12:15 PM, Simon Barrett wrote:<o:p></o:p></p>
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<p class="MsoNormal">I’m trying to use the vhostmd vdsm host to access ovirt node metrics from within a VM. Vhostmd is running and updating the /dev/shm/vhostmd0 on the ovirt node.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">The part I’m stuck on is: “This disk image is exported read-only to guests. Guests can read the disk image to see metrics” from
<a href="http://www.ovirt.org/develop/developer-guide/vdsm/hook/vhostmd/">http://www.ovirt.org/develop/developer-guide/vdsm/hook/vhostmd/</a><o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Does the hook do this by default? I don’t see any new read-only device mounted in the guest. Is there additional work I need to do to mount this and access the data from within the guest?<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Many thanks,<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Simon<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman ,serif",serif"><br>
<br>
<br>
<br>
</span><o:p></o:p></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>Users mailing list<o:p></o:p></pre>
<pre><a href="mailto:Users@ovirt.org">Users@ovirt.org</a><o:p></o:p></pre>
<pre><a href="http://lists.ovirt.org/mailman/listinfo/users">http://lists.ovirt.org/mailman/listinfo/users</a><o:p></o:p></pre>
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<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman ,serif",serif"> </span><o:p></o:p></p>
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