Product and Software: This article applies to Aruba controllers running Aruba OS 3.3.x.
Since Aruba OS 3.3.x, the secret/key/password encryption alogrithm has been enhanced and not backward compatible with older releases.
To downgrade an Aruba controller running on Aruba OS 3.3.x to 3.1.x, you should have a configuration file of the 3.1.x code version. Also, the next partition, which is not the boot partition, should contain the Aruba OS 3.1.x code version.
To downgrade, follow these steps:
1) Specify the 3.1.x configuration file as the default boot configuration file - either using "boot config-file <3.1_config_filename>" or "copy flash: <3.1_config_filename> flash: default.cfg".
2) Specify the partition that contains the 3.1.x code version as the default boot partition.
3) Reload the controller - Make sure you don't save the configuration at this moment because the specified configuration file will be overwritten by the current 3.3.x from controller memory.
Similarly, you should perform these same steps to downgrade to Aruba OS 2.5.x from 3.x.