CMMVC1200e The command failed as adding another I/O group requires compatibility mode to be enabled.

Explanation
Adding a second I/O group to the system prevents certain features from being used and
may prevent future upgrades. Features in recent code versions enable much of the functionality that
was previously available only in systems with multiple I/O groups for systems that are partnered.
For example, high-availability and migration.

User response
Review the objective of what is trying to be achieved by adding another I/O group and
determine whether newer functions can be used instead, by creating a new system and partnering the
two systems. If the newer functionality cannot be used, support for adding more I/O groups can be
enabled by enabling the compatibility mode.