3.3 KiB
Ceph keyring from file example
OpenStack-Ansible (OSA) allows to deploy an OpenStack environment that uses an existing Ceph cluster for block storage for images, volumes and instances. Interaction with the Ceph cluster is normally done using SSH to Ceph MONs. To avoid the SSH access to the Ceph cluster nodes all necessary client configurations can be read from files. This example describes what these files need to contain.
This example has just a single main requirement. You need to configure a storage network in your OpenStack environment. Both Ceph services - the MONs and the OSDs - need to be connected to this storage network, too. On the OpenStack side you need to connect the affected services to the storage network. Glance to store images in Ceph, Cinder to create volumes in Ceph and in most cases the compute nodes to use volumes and maybe store ephemeral discs in Ceph.
Network configuration assumptions
The following CIDR assignments are used for this environment.
| Network | CIDR |
|---|---|
| Storage Network | 172.29.244.0/22 |
IP assignments
The following host name and IP address assignments are used for this environment.
| Host name | Storage IP |
|---|---|
| ceph1 | 172.29.244.18 |
| ceph2 | 172.29.244.19 |
| ceph3 | 172.29.244.20 |
Configuration
Environment customizations
For a ceph environment, you can run the cinder-volume in
a container. By default cinder-volume runs on the host. See
here
an example how to a service in a container.
User variables
The /etc/openstack_deploy/user_variables.yml file
defines the global overrides for the default variables.
For this example environment, we configure an existing Ceph cluster,
that we want the OpenStack environment to connect to. Your
/etc/openstack_deploy/user_variables.yml must have the
following content to configure ceph for images, volumes and instances.
If not all necessary block storages should be provided from the Ceph
backend, do only include the block storage you want to store in
Ceph:
../../examples/user_variables.yml.ceph-config.example
Ceph keyrings
With the above settings in the
/etc/openstack_deploy/user_variables.yml we configured to
read the credentials for accessing the Ceph cluster in the
/etc/openstack_deploy/ceph-keyrings/ directory. We need to
place now the keyring files for Ceph credentials into this directory.
They need to be named according to the ceph client names, e.g.
glance.keyring according to
glance_ceph_client: glance. See the following example for
the file contents:
../../examples/ceph-keyrings/glance.keyring.example