Best would be to work with Aruba TAC to get the most optimal upgrade path.
If the release notes mention a specific upgrade path, I would follow that, despite that the update is offered in the online update.
I think that if you have an additional 1TB disk added during a major version upgrade (like 6.8.x -> 6.9; or 6.9 -> 6.10), the new disk will be used for the new installation and you can remove the old disk afterwards. But that is also something you may need to check in the documentation, or better with Aruba Support.
Backups are restored by default on the same version, but you can during the restore tick the option to disable the version check. Having said that, you could try to deploy a brand new 6.10 appliance (or consider 6.11 because it requires a operating system upgrade anyway, and you can take the opportunity now to avoid another re-installation in the near future when you move from 6.10 to 6.11); then try to restore the backup from your existing system. If that works fine (test it), you may have the fastest upgrade with the least downtime.
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Herman Robers
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If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
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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