I installed Pidora a moment ago and I realise there are tons predefined rules allowing various access. Does anyone know why? Where are all those rules from.
Fedora comes with a bunch of rules since changed frontend to firewalld. You can manage them using firewall-cmd (man firewall-cmd or just typing firewalld gives you the help.)
It's just weird to install a new OS just to see loads of rules predefined. Why did these guys not stick to iptables as firewall? IPtables works just fine on wheezy. Looks like I must spend time looking at firewall-cmd to understand how to deal with those predefined rules.
firewalld ist just kind of frontend to iptables. You still can use iptables from cmd-shell. If you want to stick on iptables, just do a systemctl disable firewalld.service, make sure to have systemctl iptables.service enabled