Open Stack

Answers in line.

From: Trivedi, Narendra [mailto:Narendra.Trivedi at savvis.com]
Sent: Tuesday, November 12, 2013 9:24 AM
To: openstack at lists.openstack.org
Subject: [Openstack] Cinde muti-backend feature

Hi All,

Could someone please explain the Cinder multi-backends feature (as of Havana)? Specifically, I had the following questions:


1)      Can I attach multiple physical storage backends (let's say one all SSD, another all SATA for instance) to a single host?
Yes. A typical cinder.conf would look like:
enabled_backends=lvmdriver-3par,lvmdriver-netapp
auth_strategy = keystone
scheduler_driver=cinder.scheduler.filter_scheduler.FilterScheduler
[lvmdriver-3par]
volume_group=cinder-volumes-3par
volume_driver=cinder.volume.drivers.lvm.LVMISCSIDriver
volume_backend_name=LVM_3par
[lvmdriver-netapp]
volume_group=cinder-volumes-netapp
volume_driver=cinder.volume.drivers.lvm.LVMISCSIDriver
volume_backend_name=LVM_netapp



2)      How does migration between different multiple backends work? Let's say the an SSD volume is attached to a VM I want to migrate all the data in the SSD volume to a SATA volume without bringing down the interface. Do I have to manually mount/un-mount the persistent volume to the instance- how do paths are maintained? For instance, let's say the persistent volume was /dev/vdx mounted to /mnt/vol0 , how does it re-appear ?
As far as I know, you have to manually copy it from one block storage to the other by mounting the new one.

Thanks a lot in advance!
Narendra



This message contains information which may be confidential and/or privileged. Unless you are the intended recipient (or authorized to receive for the intended recipient), you may not read, use, copy or disclose to anyone the message or any information contained in the message. If you have received the message in error, please advise the sender by reply e-mail and delete the message and any attachment(s) thereto without retaining any copies.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack/attachments/20131112/7aa6d72f/attachment.html>