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Hi Bryan,

The volumes should appear in the guest under /dev/xvd<num> when they are added.

As long as the guest has PV drivers it should work - so HVM guests (such as Windows or if you have installed Linux as HVM) with PV drivers will also see these volumes added (although clearly with Windows they don't show up under /dev!)

If using iSCSI then the target should appear on the xenserver host as a PBD - so "xe pbd-list" should show one up.  The code that creates this is https://github.com/openstack/nova/blob/master/nova/virt/xenapi/volume_utils.py#L51 - although that's not too obvious because we actually create a XenServer SR and allow that to create the iscsi connection.

You're right that xensm isn't supported in the current code and the docs need to be updated for Havana, but you don't have to use XenAPINFS - that SR is primarily for setups using host aggregates where you want to do in-pool migration between hosts.

Bob

> -----Original Message-----
> From: Bryan Solie [mailto:bsolie at well.com]
> Sent: 06 August 2013 13:17
> To: openstack at lists.openstack.org
> Subject: [Openstack] Cinder basic questions
> 
> I am running OpenStack grizzly on Ubuntu 12.04 with XenServer.
> 
> I have tried configuring Cinder with a few different backends, but am not
> able to get the end-to-end attachment process working.
> 
> I have tried LVM/iscsi driver: The volumes can be created.  I attach them,
> and it returns successfully.  There is an iscsi target on the Cinder host. There
> is no sign that iscsi target is logged in from the instance I have attached it to,
> and there's no indication from the CLI that it is actually attached to the
> instance.
> 
> I have tried it with xensm storage backend, which I found in the Grizzly docs.
> But this backend no longer seems supported by the code.  Not sure if this is
> out of sync somehow; I don't know the history.
> 
> I have tried it with XenapiNFS, and again, the volumes seem to be created,
> and I attach them without error, but they are not obviously visible from the
> instance.  I can't find an iscsi target when I create the volume in this case; I
> don't know whether there is supposed to be one with this driver or not.
> Code suggests no, but I am a Python newbie.
> 
> The one that seems most successful for me is the LVM/iscsi driver, but how
> do I get the volume to automatically login to the created iscsi target?
> 
> Is there a requirement to use XenapiNFS if I am on xenserver?  What are the
> advantages?  And again, how do I get created volumes to be visible from
> inside the instance?
> 
> The doc says with xenserver I can attach volumes only to paravirtualized
> guests.  I have looked at the PV-bootloader for the instances I have created,
> and it is blank.  As I understand it, they need to be on pygrub to be
> paravirtualized?  Again, I am a little new on this, and I have not been able to
> get much out of google.
> 
> Any help would be appreciated.
> 
> Bryan
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