The maximum number of IP interfaces for 5520 Series is based on the following formulas:
If you disable the VRF scaling boot configuration flag:
# IP interfaces (500 max) + (# of VRRP IPv4 interfaces) + (# of VRRP IPv6 interfaces) + (# of RSMLT interfaces) + 2(if IP Shortcuts is enabled) + 3x(# of VRFs) = cannot exceed 1000
If you enable the VRF scaling boot configuration flag:
# IP interfaces (max 500) + (# of VRRP IPv4 interfaces) + (# of VRRP IPv6 interfaces) + (# of RSMLT interfaces) + 2(if IP Shortcuts is enabled) + 3 = cannot exceed 1000