In order to block an IP on your Linux server you need to use iptables tools (administration tool for IPv4 packet filtering and NAT) and netfilter firewall. First you need to log into shell as root user. To block an IP address you need to type the iptables command as follows:
Syntax to block an IP address under Linux
Code:
iptables -A INPUT -s IP-ADDRESS -j DROP
Replace IP-ADDRESS with your actual IP address. For example, if you wish to block an ip address 65.55.44.100 for whatever reason then type the command as follows:
Code:
# iptables -A INPUT -s 65.55.44.100 -j DROP
If you have IP tables firewall script, add the above rule to your script.
If you just want to block access to one port from an ip 65.55.44.100 to port 25 then type command:
Code:
# iptables -A INPUT -s 65.55.44.100 -p tcp --destination-port 25 -j DROP
The above rule will drop all packets coming from IP 65.55.44.100 to port mail server port 25.
CentOS / RHEL / Fedora Block An IP And Save It To Config File
Type the following two command:
Code:
# iptables -A INPUT -s 65.55.44.100 -j DROP
# service iptables save
Moderator's Comments:
Use code tags, thanks.
Last edited by zaxxon; 11-06-2015 at 03:55 AM..
Reason: code tags
I have 2 LAN's, seperated by a firewall, running iptables on it.
I want only allow ftp access from one to the other LAN.
Server 1 in LAN 1 should have ftp access to Server 2 in LAN 2
Server 2 in LAN 2 should not have ftp access to Server 1 in LAN 1.
Can someone tell me how to set up the... (5 Replies)
Hi
I am looking to block an incomming IP for all the subnet in lab area. Only single Ip from Lab should be access to this incomming IP.
Block IP=10.20.50.xx
Subnet=10.30.40.xx
............................
...........................
Subnet=10.40.50.xx
can anyone explain how to do... (2 Replies)
Discussion started by: boby.kumar
2 Replies
LEARN ABOUT DEBIAN
ip6tables-apply
iptables-apply(8) System Manager's Manual iptables-apply(8)NAME
iptables-apply - a safer way to update iptables remotely
SYNOPSIS
iptables-apply [-hV] [-t timeout] ruleset-file
DESCRIPTION
iptables-apply will try to apply a new ruleset (as output by iptables-save/read by iptables-restore) to iptables, then prompt the user
whether the changes are okay. If the new ruleset cut the existing connection, the user will not be able to answer affirmatively. In this
case, the script rolls back to the previous ruleset after the timeout expired. The timeout can be set with -t.
When called as ip6tables-apply, the script will use ip6tables-save/-restore instead.
OPTIONS -t seconds, --timeout seconds
Sets the timeout after which the script will roll back to the previous ruleset.
-h, --help
Display usage information.
-V, --version
Display version information.
SEE ALSO iptables-restore(8), iptables-save(8), iptables(8).
LEGALESE
iptables-apply is copyright by Martin F. Krafft.
This manual page was written by Martin F. Krafft <madduck@madduck.net>
Permission is granted to copy, distribute and/or modify this document under the terms of the Artistic License 2.0.
2006-06-04 iptables-apply(8)
11-06-2015
