...
cas.login.url=https://${o3.cas.server.host}/cas/login
cas.logout.url=https://${o3.cas.server.host}/cas/logout?service=https://${liferay.host}/eportal
cas.validate.url=http://localhost:8280/cas/proxyValidate
<o3>/liferay/tomcat/webapps/eportal/WEB-INF/web.xml
...