CMMVC1084E The command failed as the existing I/O Group has a storage partition configured and additional I/O groups are not supported.

Explanation
A storage partition is only supported on single I/O group systems. As this feature is in
use on this system, the new I/O group cannot be added to this system.

User response
Continue to use a single I/O group system or remove the storage partition.
Alternatively, you can utilize the new nodes to set up a completely new system instead of adding
another I/O group to the current one.