OneFS requires that a node pool contain at least three nodes so that the operating system can write data and perform the necessary load balancing and data protection operations. You can enable certain nodes to be provisioned to an existing node pool by defining a compatibility.
The compatibility function is also referred to as node equivalency.
If you add fewer than three Isilon S210 or X410 nodes to your cluster, and you have existing S200 or X400 node pools, you can create compatibilities to provision the new nodes and make them functional within the cluster. Only S210 and X410 nodes are eligible for compatibility.
To be provisioned, the S210 or X410 nodes must have the same drive configurations as their S200 and X400 counterparts, and must have compatible RAM amounts, as shown in the following table:
After you have added three or more S210 or X410 nodes to your cluster, you should consider removing the compatibilities that you have created. This step enables OneFS to autoprovision new S210 or X410 node pools and take advantage of the performance specifications of the newer node types.