Chapter 4. Customizing the Red Hat Ceph Storage cluster

Procedure

1. Log in to the undercloud node as the stack user.

2. Optional: Use a standard format initialization (ini) file to configure the Ceph cluster.

   1. Create the file with configuration options.

      The following is an example of a simple configuration file:

      [global]
      osd_crush_chooseleaf type = 0
      log_file = /var/log/ceph/$cluster-$type.$id.log
      
      [mon]
      mon_cluster_log_to_syslog = true

   2. Save the configuration file.

   3. Use the openstack overcloud ceph deploy --config <configuration_file_name> command to deploy the configuration.

      Replace <configuration_file_name> with the name of the file you created.

      $ openstack overcloud ceph deploy --config initial-ceph.conf

3. Optional: Send configuration values to the cephadm bootstrap command:

   openstack overcloud ceph deploy --force \ --cephadm-extra-args '<optional_arguments>' \

   Replace <optional_arguments> with the configuration values to provide to the underlying command.

   Note

   When using the arguments --log-to-file and --skip-prepare-host, the command openstack overcloud ceph deploy --force \ --cephadm-extra-args '--log-to-file --skip-prepare-host' \ is used.

Procedure

1. Log in to the undercloud node as the stack user.

2. Generate the specification file:

   openstack overcloud ceph spec deployed_metal.yaml -o <specification_file>

   • Replace <specification_file> with the name of the file to generate with the current service specification.

     Note

     The deployed_metal.yaml comes from the output of the openstack overcloud node provision command.

3. Edit the generated file with the required configuration.

4. Deploy the custom service specification:

   openstack overcloud ceph deploy \
      deployed_metal.yaml \
      -o deployed_ceph.yaml \
      --ceph-spec <specification_file>

   • Replace <specification_file> with the name of the custom service specification file.

Procedure

1. Log in to the undercloud node as the stack user.

2. Create a YAML format file that defines the advanced OSD specification.

   The following is an example of a custom OSD specification.

   data_devices:
     rotational: 1
   db_devices:
     rotational: 0

   This example would create an OSD specification where all rotating devices will be data devices and all non-rotating devices will be used as shared devices. When the dynamic Ceph service specification is built, whatever is in the specification file is appended to the section of the specification if the service_type is osd.

3. Save the specification file.

4. Deploy the specification:

   openstack overcloud ceph deploy \ --osd-spec <osd_specification_file>

   Replace <osd_specification_file> with the name of the specification file you created.

   $ openstack overcloud ceph deploy \ --osd-spec osd_spec.yaml \