If your network runs NIS, NIS+, or LDAP, the servers for these name services maintain netmasks databases. For networks that use local files for name service, this information is maintained in the /etc/inet/netmasks file.
For compatibility with BSD-based operating systems, the file /etc/netmasks is a symbolic link to /etc/inet/netmasks.
The following example shows the /etc/inet/netmasks file for a class B network.
## The netmasks file associates Internet Protocol (IPv4) address # masks with IPv4 network numbers. # # network-number netmask # # Both the network-number and the netmasks are specified in # “decimal dot” notation, e.g: # # 220.127.116.11 255.255.255.0 18.104.22.168 255.255.255.0
If the file does not exist, create it. Use the following syntax:
Refer to the netmasks(4) man page for complete details.
When creating netmask numbers, type the network number that is assigned by the InterNIC (not the subnet number) and netmask number in /etc/inet/netmasks. Each subnet mask should be on a separate line.