Last night I was trying to undo some ip table changes I did and I ended up doing iptables -F, Is there anyway to get back to normal? I'm on an ubuntu server.
Once you delete IPtables rules, you cannot get them back.
Run these commands to delete all IPtables rules:
iptables -t raw -F iptables -t mangle -F iptables -t nat -F iptables -t filter -F iptables -t raw -X iptables -t mangle -X iptables -t nat -X iptables -t filter -X
-t is the flag for the table, there are 4 tables in IPtables. -F flushes the specified table. -X deletes all chains except the defaults in a given table.