Does CEPH 2.0 RBD support LVM ?

Latest response

I have faced instance problems over openstack which use ceph rbd as back-end storage.

I did extend volume(cinder served on CEPH RBD) from 5TB to 6TB by attaching additional 1TB cinder volume and vgextend and lvextend in Openstack instance which used LVM.

after that, with high disk busy ratio linux system fall to D-stat.

the openstack instance is RHEL 7.2, xfs filesystem.
App : postgresql 1ea, tomcat 1ea

Red Hat said, "Red Hat Ceph Storage RBD devices are not supported with LVM in CEPH 1.3".

Before extending LVM, that systems were working well.

I haven't found any documents or information not to use LVM over CEPH RBD.

Please, I need some help.

Best regards.

Responses

Hi Younghoon Chang,

I asked one of the RBD lead developers Jason Dillaman, and this is his reply:

"It sounds like LVM is being used within the guest VM — I don’t see why that wouldn’t be supported."

He also suggested to check the open file descriptor limit since you added a new RBD. See this https://access.redhat.com/solutions/1602683 solution for details.

Hope that helps!

Bara