By default, solaris will only let you add 255 IP addresses to an interface. You’ll know you hit the limit when you get an out of buffer message when you try to add your next one. In Solaris 2.5, you’re pretty much stuck with this limitation. In solaris 2.6 and higher, you can run the followng to up that limit as high as 8192. Past 8192, you’ll need to add another interface.
/usr/sbin/ndd -set /dev/ip ip_addrs_per_if 8192
