fail2ban

Bans IP that make too many password failures

Kernel

[*] Networking support  ---> 
  Networking options  --->
    [*] Network packet filtering framework (Netfilter)  --->
      Core Netfilter Configuration  --->
        [M] Netfilter Xtables support (required for ip_tables)
 
[*] Networking support  ---> 
  Networking options  --->
    [*] Network packet filtering framework (Netfilter)  --->
      Core Netfilter Configuration  --->
        IP: Netfilter Configuration  --->
          <M> IP tables support (required for filtering/masq/NAT)
          <M>   "addrtype" address type match support
          <M>   Packet filtering 
          <M>     REJECT target support