what happen in i changed the main server ip address

Hello

It depends if you are simply changing the main shared IP address for new accounts and keeping the existing IP address, or if you are completely changing the IP address that your server uses. The guide Vanessa provided should help you if you are changing an IP address completely (requires network script modification). You may also find the following option helpful after you have modified the network configuration:

"WHM Home » IP Functions » IP Migration Wizard"

Note that I suggest having your data center or a qualified system administrator assist you with the first part (modifying /etc/sysconfig/network-scripts/ifcfg-eth$) if you are not comfortable making those changes. You will also need to update your license to the new IP address.

Thank you.