This guide will help you configure Aleph to use the OpenAthens Redirector.
Whilst our service desk will always try to be helpful, they can only support the OpenAthens end. Information was correct at the time of writing.
Access the administration area as the domain administrator and navigate to the redirect link generator (Resources > Redirector link generator).
The part you are interested in is the bit like this:
Even though the redirector is not a proxy, we can use the redirector prefix in a similar way as a proxy prefix for compatible resources:
If you use a link resolver to power Aleph linking then enabling the redirector there will be the far more efficient method.
See: the link resolvers section
Unfortunately there is no simple prefix field in Aleph so your options are to manually update them one at a time, or use their bulk function as covered by them at: https://knowledge.exlibrisgroup.com/Aleph/Knowledge_Articles/Global_change_of_EZ_Proxy_URLs_in_856_tags