IPaddress is a valid IP address. mask is a Classless Inter-Domain Routing (CIDR) mask.
You can use VirtualAddressInterface to configure a mirror virtual IP address (VIP) so that all external clients (language bindings, ODBC/JDBC/SQL clients, and so on) connect to the mirror through a single address. For more information, see the Configuring a Mirror Virtual IP (VIP) section of the chapter “Mirroring” in the High Availability Guide.
Changing This Parameter
On the Create a Mirror page of the Management Portal (System Administration > Configuration > Mirror Settings > Create a Mirror) select Use Virtual IP. Then, enter an IP address and a Mask (CIDR format), and select a Network Interface.
Instead of using the Management Portal, you can change VirtualAddressInterface in the Config.MirrorMember class (as described in the class reference) or by editing the CPF in a text editor (as described in the Editing the Active CPF section of the “Introduction to the Configuration Parameter File” chapter in this book).