A 200/Success message means that the passphrase has been changed successfully; if it was unsuccessful, you would get an error message.
If you want to know if the change has been replicated to the device, you may need to find an API call to check the device synchronization status; don't have the exact call at hand.
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Herman Robers
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If you have urgent issues, always contact your HPE Aruba Networking partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact HPE Aruba Networking TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or HPE Aruba Networking.
In case your problem is solved, please invest the time to post a follow-up with the information on how you solved it. Others can benefit from that.
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