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Obtain the Yale CAS Server 2.x zip distribution from the link above. Unzip.
Other resources
There are articles which may also help you getting started deploying CAS Server. The ESUP-Portail Quick start distribution may also be a better way to get started with CAS Server. You could always read the README distributed with CAS Server.
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Of course, this requires that your cacerts contains a key, self-signed or otherwise, for your server. There's more documentation on SSL certificate issues here.
Installing the .war into Tomcat
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