How can I safely reset my network settings?

[zahtar]

Hello everyone! Following the situation on this topic,

https://www.kubuntuforums.net/forum/...ering-password

I contacted the nordvpn support and the representative asked me to enter these commands, which I do not understand how safe they are.

Am I cancelling any protection from my pc this way?

sudo iptables -F INPUT
sudo iptables -F OUTPUT
sudo iptables -P INPUT ACCEPT
sudo iptables -P OUTPUT ACCEPT
sudo iptables -F -t mangle
sudo systemctl restart NetworkManager​

Any help is appreciated!

Thanks in advance!


---------------------------------------------- EDIT ----------------------------------------------
I have still not entered the above commands, as I do not understand what they do. Nevertheless I have found a new workaround. For anyone who might face this problem here is what currently works for me:

nordvpn set killswitch on
nordvpn set autoconnect on
​

What this does is that it activates the killswitch and asks the nordvpn client to connect to a random server. This way, after entering the user password I will login without delay. If any of the above two is not enabled, I will get the 3minute delay. Therefore, both need to be active. This is the way I have kept them the last few days and they seem to do the job.

Happy new year!

[toad]

Haven't read the topic you referred to but I wouldn't to what their support suggested ...

Here a bit of AI wisdom:

What these commands do:

1. sudo iptables -F INPUT/OUTPUT: "Flushes" or deletes all existing rules in the incoming and outgoing queues.
2. sudo iptables -P INPUT/OUTPUT ACCEPT: Sets the default policy to "Accept." This ensures that once the rules are gone, the firewall doesn't default to "Drop Everything," which would cut your connection entirely.
3. sudo iptables -F -t mangle: Clears specialized packet alteration rules (less common, but good for a full reset).
4. sudo systemctl restart NetworkManager: Reboots the service that handles your Wi-Fi and Ethernet connections.

You are basically completely disabling your firewall!

Kubuntu usually uses UFW (Uncomplicated Firewall) to manage iptables. If you just want to reset your network firewall to a safe, standard state, it is often easier to run:

sudo ufw reset
sudo ufw enable

This clears custom rules and reverts to the standard "Block incoming, Allow outgoing" state that most users need. Following that just block/open your required ports ... But I see you've found a nice workaround