As you may know Ceph is not part of Debian Wheezy, thus QEMU-KVM was not compiled with the Ceph support (--enable-rbd with both librbd and librados).
This article is just a quick tip to detect if your QEMU-KVM has the support of Ceph.
Getting more familiar with the Ceph CLI with CRUSH.
Ceph admin API init script.
RBD images are thin-provisionned thus you don’t always know the real size of the image. Moreover, Ceph doesn’t provide any simple facility to check the real size of an image. This blog post took his inspiration from the Ceph mailing list.
Some experiment with gigantic overprovisioned RBD images.
Some figures from a RADOS bench.
The Ceph developer summit is already behind us and wow! so many good things are around the corner! During this online event, we discussed the future of the Firefly release (planned for February 2014). During the last OpenStack summit in Hong Kong, I had the opportunity to discuss with Sage a new feature that might go into Firefly. This was obviously discussed during the CDS too. His plan is to add a multi-backend functionality for the filestore. And trust me this will definitely bring Ceph to another level.
Memory leaks disappeared and CPU load dramatically reduced. Yay!
Curious? Wanna know who has a RBD device mapped?
Quick how-to on mapping/unmapping a RBD device during startup and shutdown.