Hello,
Make sure the Partner Firmware Upgrade option is enabled.
SMU -> Configuration -> Advanced Settings -> Firmware -> enable Partner Firmware Upgrade -> Apply
Once you confirm PFU is enabled power cycle both storage controllers, then check the firmware versions. While it is unusual the controllers will not let you upgrade unless you are using FTP it sometimes occurs that PFU is not correctly matched between the controllers and needs to be enabled.
If this does not resolve the issue please show the versions of each controller ( A & B) and let us know what version you are attempting to upgrade to.
Cheers,
Shawn
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