no longer able to connect to internet
 

I am no longer able to connect via the internet. I added these lines to my interfaces file:
pre-up iptables-restore < /etc/iptables.rules
post-down iptables-restore < /etc/iptables.downrules

Any ideas on why this change would have caused this? I am trying to restore iptables here.

Do your rules start off by flushing the old rules?

no. how do I do that?

To remove all added rules and chains, put these two lines at the beginning of your scripts:

If you added rules or chains in other tables besides FILTER, you need to explicitly flush them also using the '-t table' option.

Sorry - new to this. What script do I add it to?