Document URL: 

https://docs.openshift.com/container-platform/3.3/install_config/install/planning.html

Section Number and Name: 

Does not exist yet.

Describe the issue: 

I suggest adding more information to the planning guide around the OpenShift platform storage requirements. For instance, describe the relevance and sizing guidelines for /var/lib/openshift, /var/lib/docker and the docker-pool thin lv. 
In addition to that, I would suggest adding some information around storage requirements for the internal registry, metrics, logging storage requirements in this guide.


Suggestions for improvement: 

I constructed this statement based on the Atomic Host documentation (ref below):

The /var/lib/docker/ directory that lives on all nodes contains container images data, such as temporary data or the docker volumes. A separate Container Image Partition called docker-pool is formatted as an LVM thin pool by the docker-storage-setup service. It is used to store the container images. The space used by docker-pool is managed by the docker-storage-setup service. When you pull a container image from a registry, for example, the image takes up space on this partition. Container images are read-only. Once an image is launched as a container, all writes (except to mounted volumes or docker volumes) are stored in this Logical Volume (i.e. container logs).

Ref: https://access.redhat.com/documentation/en/red-hat-enterprise-linux-atomic-host/7/paged/getting-started-with-containers/chapter-7-managing-storage-with-docker-formatted-containers 

For the internal registry, metrics and aggregated container logging we could reference any existing documentation in the installation docs. It would also be nice to include any sizing guidelines here as well or instead of in the installation documentation.

Additional information: 

Internal Registry:
https://docs.openshift.com/container-platform/3.3/install_config/registry/deploy_registry_existing_clusters.html#storage-for-the-registry

https://docs.openshift.com/container-platform/3.3/architecture/infrastructure_components/image_registry.html

Metrics:
https://docs.openshift.com/container-platform/3.3/install_config/cluster_metrics.html#metrics-data-storage

Aggregating Container Logs:
https://docs.openshift.com/container-platform/3.3/install_config/aggregate_logging_sizing.html