How to advertise different gateway ip via DHCP in OpenWRT?

How to advertise a different router/gateway ip via DHCP in OpenWRT? In general, you need to configure the DHCP option with code 3 (router). (A list of all options can be found in http://www.networksorcery.com/enp/protocol/bootp/options.htm ) For example, to advise the gateway IP 192.168.1.2, you will send this option: “3,192.168.1.2” Now, for OpenWRT, you have 2 […]

How to log connections hitting certain rules in iptables on Linux?

How to log connections hitting certain rules in iptables on Linux? Like the one that are dropped because of too frequently creating SSH connections. You can create a new chain named LOGNDROP that log the connections and drop them, then pass the connection to be redirected to the LOGNDROP chain. $tables -N LOGNDROP # Connections […]

How to use iptables to limit rates new SSH incoming connections from each IP on Linux?

How to use iptables to limit rates new SSH incoming connections from each IP on Linux? For example, at most 6 SSH connection attempts every 60 seconds. You may use these rules (skip the first one, if you have set the basic rules): for tables in iptables ip6tables ; do # Allow established inbound connections […]