Glance and CEPH backend

Using CEPH as a backend for glance images has slowly become the default deployment methodology in many production deployments. It is usually as easy as creating a new pool in ceph ( glance pool) and creating a user to be associated with glance. The glance CEPH user will normally authenticate using cephx and store images … Continue reading Glance and CEPH backend


VM Cold migrations/resizing in openstack

Cold migrations are an integral piece of any QEMU/KVM deployment. It's cold or "non-live" as you have to power down the VM, move it to the new host and power it back up. Openstack follows the same procedure when it comes to migrating VMs. Cold migrations in Openstack are done via the user running the … Continue reading VM Cold migrations/resizing in openstack

OpenStack Performance tuning

So, ¬†you've managed to deploy OpenStack in a production environment, and now you would like to make sure that your precious investment in hardware doesn't get ruined by poor performance tuning. You might want to consider reading this post. You have to remember first that OpenStack is a Cloud Computing Enabler framework, i.e. none of … Continue reading OpenStack Performance tuning


Private External Networks in Neutron

You might find yourself in a position where you need to restrict access by tenants to specific external networks. In Openstack there's the notion that external networks are accessible by all tenants and anyone can attach their private router to it. This might not be the case if you want to only allow specific users … Continue reading Private External Networks in Neutron


Ceph RBD snapshots for an attached volume

You might find yourself in a scenario where you need to backup a CEPH volume attached to an Openstack Instance. CEPH snapshots come automatically to mind as the "state-in-time" solution. Once you take a CEPH snapshot, you can export it and backup the volume either as a physical file or at the file system level, … Continue reading Ceph RBD snapshots for an attached volume