About Cisco WLC, there are many interface types, as shown below, this is mainly for the Virtual IP recording some best practice recommendations.
Role Virtual IP address of the Cisco WLC:
• Mobility Management
• the DHCP relay
• Embedded L3 security (such as Guest Web authentication and VPN termination)
• It also enables Layer 3 Web authorization, maintain Layer 3 Security and Mobility Management DNS gateway host name of the device (mobility managers) used to verify the certificate of origin
Main functions:
1. The process acts as a DHCP client placeholder
2. serve as a redirect address of the Web authentication login page
Virtual IP restrictions:
1. The address is used as an exchange between Client and WLC
2. This address will not be displayed to the port from the distributed source or destination address of a distributed system network
3. In order to make the system normal operation, the address must be set (can not 0.0.0.0)
any other device on the IP network 4. the IP address can not be the same and
5. the ping the IP address is not, and should not present any routing tables in the network
6. the IP can not be mapped to a physical port
7. If in case mobility group, WLC are all the Virtual IP needs to be configured the same, otherwise, not roaming between WLC handoff is complete, the client disconnects a period of time
Under normal circumstances, we may configure the virtual IP is 1.1.1.1, but this is not currently recommended optimal configuration, refer to the following:
Virtual Gateway IP
It is recommended to configure a non-routable IP address for the virtual interface, ideally not overlapping with the network infrastructure addresses. Use one of the options proposed on RFC5737, for example, 192.0.2.0/24, 198.51.100.0/24, and 203.0.113.0/24 networks.
This should be used in most scenarios.
To change the address:
(Cisco Controller) >config interface address virtual <new address>