Various stuff I forget how I do it.
View iptables # View iptables sudo iptables -nvL Add/Remove/Replace # Add a rule iptables -A INPUT -p tcp --dport 80 -j ACCEPT # Append to end of chain iptables -I INPUT 1 -p tcp --dport 80 -j ACCEPT # Insert at position 1 in chain # Delete a rule iptables -D INPUT 5 # 5 is index 5 in the INPUT-chain # Replace a rule iptables -R INPUT 1 -p tcp -s 192.168.0.0/24 --dport 80 -j ACCEPT # Replace rule at index 1 Persisting Generally, tables are saved in
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This is a very broad title, and will probably not help anyone except for me if this happens for me again.
One day when I had to restart my KVM host, none of my guests had internet connection. The eth0 on the KVM host was attached to a bridge (br0) and that host had connectivity through the bridge. Here are some configs (which had not changed since it worked):
# /etc/network/interfaces source /etc/network/interfaces.d/* # The loopback network interface auto lo iface lo inet loopback # The primary network interface allow-hotplug eth0 iface eth0 inet manual #iface eth0 inet dhcp auto br0 iface br0 inet dhcp bridge_ports eth0 bridge_stp off bridge_fd 0 bridge_maxwait 0 Configuration seems good to me. I have never needed stp=on, so it should be alright.
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