Hi,
Virtual interface is used for certain client management functions such as DHCP request and mobility/roaming functions (every controller in the same mobility group should be configured with identical virtual address).
in other words....
Virtual Interface – This interface handles any mobility management, VPN Termination, Web authentication, and is also a DHCP relay for WLAN clients. You really want to give this interface a bogus type address (Like 1.1.1.1 or something) since it’s only accessed and used by the WLC, the APs and WLAN clients will not interact with this interface. (Other then it’s purpose as the DHCP relay, but it’s all in done within the controller unknown to the AP’s or clients).
Regards
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