Use to specify the subnet mask (in dotted decimal notation) for this Logical IP
Subnet (LIS); 255.255.192.0, for example. The logical AND of the subnet mask and
any IP address in this LIS should result in the subnet value;
255.255.192.0 AND 10.1.180.254 = 10.1.128.0, for example.
Rules:
The 32-bit subnet mask must be one or more one-bits followed by one or more zero-bits. The subnet mask cannot have any one-bits to the right of any zero-bits. Therefore, a mask of 255.255.192.0 is valid because 255 is 11111111 and 192 is 11000000, but a mask of 255.255.208.0 is not valid because 208 is 11010000.