Shell---Login failed IP add to/etc/hosts.deny

/etc/hosts.deny: Commonly known as blacklist, control remote access settings.

#!/bin/bash           //program starts #file: hosts_deny.sh# date: 2016-01-10grep  ' Failed password '  /var/log/secure | awk  ' {print $ One} '  | uniq -c | sort | //remove the log-in failed IP and sort the statistics while read a b      //reading Statistical results do    grep -q  $b  /etc/hosts.deny      //test if IP exists, exists as 0      if [ $? !=  0 ] ; then        if [  $a  -ge The number of  5 ] ; then   //statistics is greater than or equal to 5             echo  "sshd:  $b"  >> /etc/hosts.deny    // Add IP to blacklist             fi       fidone               //Program End 

This article from "Experience from pain" blog, declined reprint!

Shell---Login failed IP add to/etc/hosts.deny