Configuration guidelines
Follow these guidelines when you assign an IP address to an interface:
An interface can have only one primary IP address. A newly configured primary IP address overwrites the previous one.
You cannot assign secondary IP addresses to an interface that obtains an IP address through BOOTP, DHCP, or IP unnumbered.
The primary and secondary IP addresses assigned to the interface can be located on the same network segment. Different interfaces on your device must reside on different network segments.