There is two certificates on your clearpass Radius and HTTPS, if your radius expires you potientally, your NAD's will not be able too communciate with Clearpass. aka authenticate login etc.
If your HTTP certificate expires some internet browsers (e.g. Chrome/Edge) will not even let you get to the any clearpass pages, as default internet browsers security settings prevent you from accessing expired certificate sites.
As mentioned above put on a self signed until you get your certificates from a trusted third party.
N.B. not recommended to get a wildcard certificate for Clearpass.
Aruba Partner Network Consultant
**Aruba Wireless ACMP / ClearPass ACCP / CCNP Professional **
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