The first step in provisioning a site is creating a storage pool and assigning it nodes. Storage pools are logical constructs that contain physical nodes. They provide a means to physically separate data on a cluster, if required. Erasure coding (EC) is configured at the storage pool level during pool creation. The two EC options on ECS are 12+4 or 10+2 (cold storage). EC cannot be changed once created.
All cluster nodes can belong to a single storage pool. Implement the minimum number of storage pools required at each VDC. Storage pools along with their associated replication groups are integral in ECS indexing so keeping them to a minimum required minimizes unnecessary overhead.
There are only two reasons to create additional storage pools within a VDC:
A storage pool must have a minimum of five nodes and must have three or more nodes with more than 10% free space data/object writes to be successful. System metadata, user data and user metadata all coexist on the same disk infrastructure. Space is reserved so that ECS does not run out of space while persisting system metadata. Storage pool space considerations are also important when sites are replicated. Multi-site environments require sufficient space available to handle temporary and permanent site failures. When adding additional storage capacity to a site, expand other sites as needed to accommodate space requirements.
Storage pool best practices