ATKAAW065E: Netmask/prefix length format error. Valid format is xxx.xxx.xxx.xxx or integer in [1-128].

Explanation: For an IPv4 address, you can specify a range from 1 to 32 or you can specify a netmask in the format nnn.nnn.nnn.nnn, where nnn is a numeric value of 0-255. For an IPv6 address, specify the prefix length in a range from 1 to 128.

Operator Response: Enter a value matching a correct format.