12. How to make the loopback alias permanent in Solaris 10

This setting helps to keep the netmask to be /32 ( of the loopback alias on reboot.

Use CIDR notation specifying /32 in /etc/hostname.lo0:1, e.g.:

# cat /etc/hostname.lo0:1

Use also CIDR notation for all normal interfaces specifying the normal netmask, e.g.:

# cat /etc/hostname.bge0

And last but not least remove the network entry and corresponding netmask from /etc/netmasks.