I am logged in as a root user i want to edit my /etc/sysconfig/network-scripts/ifcfg-eth0 file when i edit this showing -- INSERT -- W10: Warning: Changing a readonly file while i have logged in as root user my mount showing

   [root@s1202 ~]# mount
   rootfs on / type rootfs (rw)
   /dev/root on / type ext3 (ro,data=ordered)
   /dev on /dev type tmpfs (rw)
   /proc on /proc type proc (rw)
   /sys on /sys type sysfs (rw)
   /proc/bus/usb on /proc/bus/usb type usbfs (rw)