Automatically update local hosts file with hosts-file.net

update-hosts.sh

#!/usr/bin/env sh
 
# Filename: update-hosts.sh
# Authors: George Lesica <george@lesica.com>
#          Danilo Fasolin Salmazio <dfasolin@gmail.com>
# Description: Replaces the HOSTS file with a customized version (hosts-file.net) that blocks
# domains that serve ads and malicious software, creating a backup of the old
# file.
# Improvements: Add the partial file, a /etc/hosts_dev with some development hosts and creates 
# a logfile
#
# hosts_dev sample:
# ########################################################
# ###################### HOSTS DEV #######################
# ########################################################
# 192.168.33.10                     dev
# 192.168.33.11                     sample-dev.com
#
# Add this file to cron with crontab -e (root access)
# sudo -s
# crontab -e
# min   hr      mday    month   wday    command
# 00    21      *       *       5       /var/root/update-hosts.sh >> /var/log/update_hosts.log 2>&1
#
# The cron execution creates a logfile in /var/log/update_hosts.log

HOSTS_URL="http://hosts-file.net/download/hosts.txt"
NEW_HOSTS="hosts"
HOSTS2_URL="http://hosts-file.net/hphosts-partial.asp"
NEW_HOSTS2="hosts2"
HOSTS_PATH="/etc/hosts"
 
# Add all dev hosts in /etc/hosts_dev file
HOSTS_DEV="/etc/hosts_dev"
LOGFILE="/var/log/update_hosts.log"
 
# Check for root
if [ "$(id -u)" -ne "0" ]; then
    echo "This script must be run as root" 1>&2
    exit 1
fi

# Remove the old LOGFILE
rm -f $LOGFILE

# Grab hosts files
/usr/local/bin/wget -O $NEW_HOSTS $HOSTS_URL
/usr/local/bin/wget -O $NEW_HOSTS2 $HOSTS2_URL

# Remove old Backup and create a new one of hosts file
rm -f ${HOSTS_PATH}.bak*
cp -v $HOSTS_PATH ${HOSTS_PATH}.bak$(date -u +%s)
cp -v $NEW_HOSTS $HOSTS_PATH

# Add the diff and developer hosts
/bin/cat $NEW_HOSTS2 >> $HOSTS_PATH
/bin/cat $HOSTS_DEV >> $HOSTS_PATH

# Clean up old downloads
rm $NEW_HOSTS*