update-hosts.sh

#!/bin/sh

TARGET='/etc/hosts'
SOURCE="$HOME/hosts"
BACKUP="$HOME/hosts.$(date +'%Y-%m-%d').bak"

#BACKUP
cp "$TARGET" "$BACKUP"

#DOWNLOAD NEW
wget -q -O "$SOURCE" "https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts"

#REFRESH EXISTING TERGET
sudo rm "$TARGET"
sudo touch "$TARGET"

#ADD DEFAULT VALUES
echo '127.0.0.1 localhost' | sudo tee -a "$TARGET" >/dev/null
echo '127.0.0.1 local' | sudo tee -a "$TARGET" >/dev/null
echo '127.0.0.1 dev' | sudo tee -a "$TARGET" >/dev/null
echo "127.0.0.1 $(hostname)" | sudo tee -a "$TARGET" >/dev/null
echo '::1       ip6-localhost ip6-loopback' | sudo tee -a "$TARGET" >/dev/null
echo 'fe00::0   ip6-localnet' | sudo tee -a "$TARGET" >/dev/null
echo 'ff00::0   ip6-mcastprefix' | sudo tee -a "$TARGET" >/dev/null
echo 'ff02::1   ip6-allnodes' | sudo tee -a "$TARGET" >/dev/null
echo 'ff02::2   ip6-allrouters' | sudo tee -a "$TARGET" >/dev/null

#ADD NEW STUFF
sudo tee -a "$TARGET" >/dev/null <"$SOURCE"