Define multiple certificates in an SSL profile in replace mode

Multiple certificates can be defined in an SSL inspection profile in replace mode (Protecting SSL Server). This allows multiple sites to be deployed on the same protected server IP address, and inspection based on matching the SNI in the certificate.

When the FortiGate receives the client and server hello messages, it will compare the SNI and CN with the certificate list in the SSL profile, and use the matched certificate as a replacement. If there is no matched server certificate in the list, then the first server certificate in the list is used as a replacement.

Example

To configure an SSL profile in replace mode with multiple certificates:

config firewall ssl-ssh-profile
    edit "multi-cert"
        set server-cert-mode replace
        set server-cert "bbb" "aaa"
    next
end

To configure a policy that uses the SSL profile:

config firewall policy
    edit 1
        set name "multi-cert"
        set srcintf "port6"
        set dstintf "port11"
        set srcaddr "all"
        set dstaddr "all"
        set action accept
        set schedule "always"
        set service "ALL"
        set utm-status enable
        set ssl-ssh-profile "multi-cert"
        set av-profile "default"
        set webfilter-profile "default"
        set logtraffic all
        set nat enable
    next
end

Results

If the Server Name Identification (SNI) matches the Common Name (CN) in the certificate list in the SSL profile, then the FortiGate uses the matched server certificate. In this example, when the client accesses www.aaa.com, the FortiGate will use the aaa certificate as a replacement.

If the Server Name Identification (SNI) does not match the Common Name (CN) in the certificate list in the SSL profile, then the FortiGate uses the first server certificate in the list. In this example, when the client accesses www.ccc.com, because there is no certificate for www.ccc.com, the FortiGate will use the bbb certificate as a replacement.