[HELP] the system cannot login after set the iptables rules.

[Mogei Wang]

Hello everyone,
I am a newcomer to ubuntu, and boot my ubuntu from the windows grub.
Days before, I have set the iptables rules, and then the ubuntu cannot login.

In detail, I
(1) added the rules to the file /etc/iptables.up.rules ;
(2) added the following two lines to the file /etc/network/interfaces
pre-up iptables-restore < /etc/iptables.up.rules
post-down iptables-save > /etc/iptables.up.rules
(3) reboot the computer.

Then, I found that the system cannot login.

In the boot process, the last message I can see is "Begin: Running
/scripts/init_bottom... "
Then, the screen flashes black, and the cursor stops.
Since I had turn the KMS off, I do not think it is the problem of graph.
Moreover, it seems okay to switch between the ttys.
I believe it is because that the iptables rules are wrong, or because
the iptables-restore / iptables-save.
.
However, I cannot login the system to change the rules.

I have tried the following ways:
(1) try to use the ubuntu harddisk install. However, I cannot access
the ubuntu filesystem in such a way.
(2) push the [shift] key during the system booting. Nothing changed.
(3) change the grub menu.lst
kernel /boot/vmlinuz-*-generic root=/dev/sda* ro rescue single
Still nothing changed.

So how can I do now?

You are welcome!

Yours mogei