We want to buy a certificate SSL to change the actual certificate in ASA. Are there any requirement or specific type of certicate compatible with ASA?
Check this document
Supported 3rd party CA vendors are Baltimore, Cisco, Entrust, iPlanet/Netscape, Microsoft, RSA, and VeriSign. So if you want some support from Cisco it should be some certificate from those vendors but we successfully used also certificate from other vendor.. Generally it should be any X.509 certificate
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