不定项选择题 9.  By default, which kind of certificate does the ISR create upon each reboot that will cause client warnings when attempting SSL VPN access because the certificate cannot be verified?默认情况下，ISR会在每次重启之后生成哪种证书?但是由于该证书无法被验证，因此客户端在试图进行SSL VPN访问时会收到证书警告。