how u use the iptable firewall to restrict ssh,telnet,ftp
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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
| Is This Answer Correct ? | 26 Yes | 0 No |
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
| Is This Answer Correct ? | 12 Yes | 0 No |
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
| Is This Answer Correct ? | 6 Yes | 0 No |
Answer / srivathsan
Just a small typo to the file name, it is '/etc/hosts.deny'
Thanks,
- Vathsan.
| Is This Answer Correct ? | 5 Yes | 2 No |
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
| Is This Answer Correct ? | 2 Yes | 0 No |
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.
| Is This Answer Correct ? | 4 Yes | 3 No |
Answer / nrupan mampilly
iptables -I INPUT -t filter -s source -p protocol --dport
portnumber -j REJECT
| Is This Answer Correct ? | 0 Yes | 0 No |
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.
| Is This Answer Correct ? | 1 Yes | 15 No |
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