On 16/05, Mohammed Naser wrote:

On Thu, May 16, 2019 at 2:14 AM Gary Molenkamp <molenkam@uwo.ca> wrote:

...

I am moving my cinder-volume service from one controller to another, and I'm trying to determine the correct means to update all existing volume's back-end host reference. I now have two cinder volume services running in front of the same ceph cluster, and I would like to retire the old cinder-volume service.

For example, on my test cloud, "openstack volume service list":

+------------------+----------------------------------+------+---------+-------+----------------------------+ | Binary | Host | Zone | Status | State | Updated At | +------------------+----------------------------------+------+---------+-------+----------------------------+ | cinder-scheduler | osdev-ctrl1 | nova | enabled | up | 2019-05-15T17:44:05.000000 | | cinder-volume | osdev-ctrl2@rbd | nova | disabled | up | 2019-05-15T17:44:04.000000 | | cinder-volume | osdev-ctrl1@rbd | nova | enabled | up | 2019-05-15T17:44:00.000000 | +------------------+----------------------------------+------+---------+-------+----------------------------+

Now, an existing volume has a reference to the disabled cinder-volume: "os-vol-host-attr:host | osdev-ctrl2@rbd#rbd"

but this needs to be changed to: "os-vol-host-attr:host | osdev-ctrl1@rbd#rbd"

As both controllers are members of the same ceph cluster, an "openstack volume migrate" is not appropriate. If it is appropriate, my testing has shown that it errors out and deletes the source volume from ceph.

I can alter this field manually in the cinder database, but in following the "don't mess with the data model" mantra, is there a means to do this from the cli?

https://docs.openstack.org/cinder/stein/cli/cinder-manage.html#cinder-volume

cinder-manage volume update_host --currenthost <current host> --newhost <new host>

That should do it :)

Hi, Since you've already create volumes in the new cinder-volume service Mohammed's suggestion is the right one. For the future, when you want to move the service to a new node, I would recommend you setting the 'backend_host' configuration option in the driver's section or the 'host' option in the DEFAULT section. That way you don't need to modify the database and the service will start with the same host as the old one regardless of where you are running it. This is the recommended way to deploy Cinder-Volume in Active-Passive, as you won't need to make any changes when you start the service on a new node. Cheers, Gorka.

...

Thanks, Gary.

Openstack release: Queens. Distro: Redhat (Centos) 7.6

-- Gary Molenkamp Computer Science/Science Technology Services Systems Administrator University of Western Ontario molenkam@uwo.ca http://www.csd.uwo.ca (519) 661-2111 x86882 (519) 661-3566

-- Mohammed Naser — vexxhost ----------------------------------------------------- D. 514-316-8872 D. 800-910-1726 ext. 200 E. mnaser@vexxhost.com W. http://vexxhost.com