[root@centos ~]# vi /etc/postfix/main.cf
↓最終行に下記を記入
# Virtual configuration
virtual_alias_maps = hash:/etc/postfix/virtual
[root@centos ~]# vi /etc/postfix/virtual
↓最終行に下記を記入
example.com anything
user_name@example.com user_name
[root@centos ~]# postmap /etc/postfix/virtual
[root@centos ~]# /etc/rc.d/init.d/postfix reload