That's interesting:
Aruba 5412R zl2 (KB.16.05.0007, thus a not too recent software release):
A5412Rzl2(config)# power-over-ethernet
poe-reset Use this command to reset the PoE controller to which the port belongs.
pre-std-detect Detect and power pre-802.3af-standard devices.
redundancy Set how much power is held in reserve for redundancy.
slot Optional - Specify a valid powered-slot list for power threshold setting or omit to set all powered-slots.
threshold Set the threshold at which the system will send an excess power consumption notification trap.
Now on a VSF made of two Aruba 5406R zl2 (running the very same software version):
A5406Rzl2-VSF(config)# power-over-ethernet
poe-reset Use this command to reset the PoE controller to which the port belongs.
pre-std-detect Detect and power pre-802.3af-standard devices on the specified stack members or member to set on all members
slot Optional - Specify a valid powered-slot list for power threshold setting or omit to set all powered-slots.
threshold Set the threshold at which the system will send an excess power consumption notification trap.
vsf Set PoE configuration for the specified members.
So the power-over-ethernet redudancy option seems to be not available on my Aruba 5406R zl2...and I don't think this absence is due to VSF deployment scenario (2x5406R)versus a Standalone scenario (1x5412R) since the Power Supplies PoE redundancy option should be tied, as a feature, to the chassis operation and it should be independent by VSF scenarios versus Standalone scenarios.
Clearly we have the maximum numbers of Power Supplies installed on both scenarios:
A5412Rzl2# show system power-supply
Power Supply Status:
PS# Model Serial State AC/DC + V Wattage
---- --------- ------------ ----------------- -------------- ---------
1 J9829A CN6AK36xxx Powered AC 120V/240V 1100
2 J9829A CN6AK36xxx Powered AC 120V/240V 1100
3 J9829A CN6AK36xxx Powered AC 120V/240V 1100
4 J9829A CN6AK36xxx Powered AC 120V/240V 1100
4 / 4 supply bays delivering power.
Total power: 4400 W
A5406Rzl2-VSF# show system power-supply
Power Supply Status:
VSF
Member PS# Model Serial State AC/DC + V Wattage Max
------- ----- --------- ----------- --------------- ----------------- --------- ------
1 1 J9829A CN6AK36xxx Powered AC 120V/240V 45 1100
1 2 J9829A CN6AK36xxx Powered AC 120V/240V 48 1100
2 1 J9829A CN6AK36xxx Powered AC 120V/240V 45 1100
2 2 J9829A CN6AK36xxx Powered AC 120V/240V 49 1100