If you want to block the entire class a network, add the following to your .htaccess
Code
<Limit GET HEAD POST>
order allow,deny
allow from all

# Broad violator range
deny from 47.0.0.0/8
</Limit>


If you want be more specific, add the following to your .htaccess
Code
<Limit GET HEAD POST>
order allow,deny
allow from all

# Singapore common violator ranges
deny from 47.74
deny from 47.79
deny from 47.82
deny from 47.84
deny from 47.88
deny from 47.89
</Limit>


If you want be more near exact in what you limit, add the following to your .htaccess
Code
<Limit GET HEAD POST>
order allow,deny
allow from all

# Singapore specific
deny from 47.74.128.0/17
deny from 47.79.0.0/20
deny from 47.79.48.0/20
deny from 47.79.96.0/19
deny from 47.79.192.0/18
deny from 47.82.0.0/18
deny from 47.84.0.0/16
deny from 47.88.128.0/17
deny from 47.89.88.0/24
deny from 47.89.91.0/24
deny from 47.128.0.0/14
deny from 47.235.1.0/24
deny from 47.235.4.0/24
deny from 47.235.6.0/23
deny from 47.235.19.0/24
deny from 47.235.21.0/24
deny from 47.235.30.0/24
deny from 47.236.0.0/15
deny from 47.241.0.0/16
deny from 47.245.64.0/18
deny from 47.246.1.0/24
deny from 47.246.39.0/24
deny from 47.246.58.0/24
deny from 47.246.62.0/23
deny from 47.246.106.0/24
deny from 47.246.157.0/24
deny from 47.246.158.0/23
deny from 47.246.160.0/20
deny from 47.246.196.0/22
</Limit>

source for country list
IP2Location - Block Visitors by Country
https://www.ip2location.com/free/visitor-blocker

TO AVOID POSSIBLE HOST VIOLATIONS, DO NOT ADD TOO MANY DENY REQUESTS

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