Question : How to update subnet mask in a unix box

I need to update the subnet mask on my UNIX box. Which file should be updated?

Answer : How to update subnet mask in a unix box

as NetExpert-Warszawa mentioned, add

172.25.116.128   255.255.255.224

to /etc/netmasks , e.g.

echo "172.25.116.128   255.255.255.224" >>  /etc/netmasks