Answer / sins

simply use..... iptables -A INPUT -s <sourse ip or n/w u
want to block the services> -p tcp --dport <specify prt
number> -j REJECT/DROP/DENY

Answer / rajesh dwivedi

If you restrict ssh/telnet or ftp u have to write a rule
for example u have to restrict ssh

IPTABLES -A INPUT -p tcp -s <IP Address or Domain IP> --
dport <ssh port> -j REJECT/DROP

Answer / saurabh makkar

For SSH
iptables -A INPUT -s <sourse ip or n/w u
want to block the services> -p tcp --dport <22> -j
REJECT/DROP/DENY

For Telnet
iptables -A INPUT -s <sourse ip or n/w u
want to block the services> -p tcp --dport <23> -j
REJECT/DROP/DENY

For FTP
iptables -A INPUT -s <sourse ip or n/w u
want to block the services> -p tcp --dport <21> -j
REJECT/DROP/DENY

Answer / srivathsan

Just a small typo to the file name, it is '/etc/hosts.deny'

Thanks,

- Vathsan.

Answer / swapnil

if want to put on the INPUT then
iptables -A INPUT -s source -p protocol --dport destination
port -j DENY
if want to put the OUTPUT tables then
iptables -A OUTPUT -s source -p protocol --dport denation
port -j DENY

Answer / srivathsan

Followed by iptables command mentioned by Sins to restrict
domains for various services, pleaese run
$ service iptables save
$ restorecon /etc/sysconfig/iptables.

Also, you could block the domains by adding an entry inside
/etc/hots.deny like,

sshd: <Unwanted domain url>

:qw to save changes to the file.

- Vathsan.

Answer / nrupan mampilly

iptables -I INPUT -t filter -s source -p protocol --dport
portnumber -j REJECT

Answer / sanjay

service iptables start
iptables on

Answer / anil kumar pinnaka

chkconfig --level < run level for enabling the iptables > on

This will enables the ip table for the given run level.

so that these service will ge blocked.

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