Hi friends, recently i had configured my linux PC to work as DHCP server... everything was fine... but after 4 days... now when i boot in FC4 it is uncompressing linux correctly and initrd is also fine.... but "applying iptables and firewall rules" system is hanging here... even ctrl+alt+del is not working.. i tried 5 times.. same thing is happening for smp also.. i have some impt data in FC4 please help me to get that data back....
thanks...

Try booting the system in single user mode and check if there is any problem with iptables rules. If you need those imp data, then disable the iptables at single user mode and switch init to 3 or 5 and recover those data.

thanks for reply kutty_prasad,
but how to switch to single user mode ??? and what do u mean by switching init to 3 or 5 ????

1.) Single user mode.

When you get the boot menu after a reboot, press the key "e" on you keyboard and then select the line which states the vmlinuz and initrd and again press "e". Now you should be able to edit the line. Go to end of the line and add "1" (number one without quotes) after a space. Press enter and then press "b" key.

2.) Now you should be in single user mode. Type "chkconfig iptables off" (this will disable the iptables services, use "chkconfig iptables on" to enable the service later). Then type "init 5" to start as normal.

init 5 - to boot into GUI mode with all the serivces.
init 3 - same a 5, except GUI will not be loaded.

Hope this helps.