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<P><FONT SIZE=2>Thank you for the information :-)<BR>
<BR>
I never used Ceph RDB before but we will have a look into it to consider if this is an option for us.<BR>
<BR>
Regards,<BR>
Michael<BR>
<BR>
-----Ursprüngliche Nachricht-----<BR>
Von: Jonathan D. Proulx [<A HREF="mailto:jon@csail.mit.edu">mailto:jon@csail.mit.edu</A>]<BR>
Gesendet: Dienstag, 21. Juni 2016 16:51<BR>
An: Michael Stang<BR>
Cc: Matt Jarvis; OpenStack Operators<BR>
Betreff: Re: [Openstack-operators] Shared Storage for compute nodes<BR>
<BR>
On Tue, Jun 21, 2016 at 11:42:45AM +0200, Michael Stang wrote:<BR>
:I think I have asked my question not correctly, it is not for the cinder :backend, I meant the shared storage for the instances which is shared by the :compute nodes. Or can cinder also be used for this? Sorry if I ask stupid :questions, OpenStack is still new for me ;-)<BR>
<BR>
<BR>
We use Ceph RBD for:<BR>
<BR>
Nova ephemeral storage<BR>
Cinder Volume storage<BR>
Glance Image storage<BR>
<BR>
(and ceph for object storage too)<BR>
<BR>
/var/lib/nova which holds the libvirt xml files that actually define instances live on local node staorage.<BR>
<BR>
This is sufficient for us to do live migration. However as of Kilo at least 'vacating' a failed node doesn't work as it assumes /var/lib/nova is on shared storage if the ephemeral storage is shared even though the xml could be recreated from the database. I don't know if Juno or Mitaka still have this issue or not.<BR>
<BR>
If I were trying to solve that I'd probably go with NFS for /var/lib/nova as it's easy, storage is small (just text files) and load is light. But we've been very happy with ceph rbd for ephemeral storage.<BR>
<BR>
Our use case is private cloud w/ 80 hypervisors and about 1k running VMs supported by a team of two (each of whom has other responsibilites as well). Ceph is 3 monitors and 9 storage nodes with 370T raw storage ( with triple replication net storage is 1/3 of that.)<BR>
<BR>
-Jon<BR>
<BR>
:<BR>
:Regards,<BR>
:Michael<BR>
:<BR>
:<BR>
:> Matt Jarvis <matt.jarvis@datacentred.co.uk> hat am 21. Juni 2016 um 10:21 :> geschrieben:<BR>
:><BR>
:> If you look at the user survey (<BR>
:> <A HREF="https://www.openstack.org/user-survey/survey-2016-q1/landing">https://www.openstack.org/user-survey/survey-2016-q1/landing</A> ) you can see :> what the current landscape looks like in terms of deployments. Ceph is by far :> the most commonly used storage backend for Cinder.<BR>
:><BR>
:> On 21 June 2016 at 08:27, Michael Stang <michael.stang@dhbw-mannheim.de :> <A HREF="mailto:michael.stang@dhbw-mannheim.de">mailto:michael.stang@dhbw-mannheim.de</A> > wrote:<BR>
:> > > Hi,<BR>
:> > <BR>
:> > I wonder what is the recommendation for a shared storage for the compute<BR>
:> > nodes? At the moment we are using an iSCSI device which is served to all :> > compute nodes with multipath, the filesystem is OCFS2. But this makes it a :> > little unflexible in my opinion, because you have to decide how many compute :> > nodes you will have in the future.<BR>
:> > <BR>
:> > So is there any suggestion which kind of shared storage to use for the<BR>
:> > compute nodes and what filesystem?<BR>
:> > <BR>
:> > Thanky,<BR>
:> > Michael<BR>
:> > <BR>
:> ><BR>
:> > _______________________________________________<BR>
:> > OpenStack-operators mailing list<BR>
:> > OpenStack-operators@lists.openstack.org<BR>
:> > <A HREF="mailto:OpenStack-operators@lists.openstack.org">mailto:OpenStack-operators@lists.openstack.org</A><BR>
:> > <A HREF="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators</A><BR>
:> > ><BR>
:> DataCentred Limited registered in England and Wales no. 05611763 :><BR>
:<BR>
:<BR>
:Viele Grüße<BR>
:<BR>
:Michael Stang<BR>
:Laboringenieur, Dipl. Inf. (FH)<BR>
:<BR>
:Duale Hochschule Baden-Württemberg Mannheim :Baden-Wuerttemberg Cooperative State University Mannheim :ZeMath Zentrum für mathematisch-naturwissenschaftliches Basiswissen :Fachbereich Informatik, Fakultät Technik :Coblitzallee 1-9<BR>
:68163 Mannheim<BR>
:<BR>
:Tel.: +49 (0)621 4105 - 1367<BR>
:michael.stang@dhbw-mannheim.de<BR>
:<A HREF="http://www.dhbw-mannheim.de">http://www.dhbw-mannheim.de</A><BR>
<BR>
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