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Block and Allow IP using iptables in RedHat Linux 4.0

Dear Friend

I have blocked below IP by using iptables command in RedHat Linux 4.0.

Code:

iptables -A INPUT -s 192.168.0.85 -j DROP

It's now totally blocked and can't get access into web or internal network.

Please let me know how I can un-block that IP, so that it can again starts it's normal operation.

Appreciate, if you would come back at your earliest.

Regards
Pervez

Greetings,

Pervez,

To remove a block:
- ssh to the machine that has blocked the user.

- If you need to, you can search the firewall for just that IP address with:

Quote:

sudo /sbin/iptables --list --numeric --verbose | /bin/grep ipaddr, e.g.
sudo /sbin/iptables --list --numeric --verbose | /bin/grep 152.2.129.83

- When you have decided that the address is indeed blocked by the firewall,
run the following command:

Quote:

sudo /sbin/iptables --delete rule -s ipaddr/32 -d 0/0 -j DROP, e.g.
sudo /sbin/iptables --delete UNC-ACCEPT-INPUT -s 152.2.129.83/32 -d 0/0 -j DROP

- Now search for the IP address again in UNC-ACCEPT-INPUT, in case the user
ended up in the firewall more than once. All instances of the IP address
must be removed from the UNC-ACCEPT-INPUT firewall rule.

All the best

Quote:

Originally Posted by mostafaashish (Post 3629338)

Dear Friend

I have blocked below IP by using iptables command in RedHat Linux 4.0.

Code:

iptables -A INPUT -s 192.168.0.85 -j DROP

couple of ways.

1. service iptables restart
2. iptables --list INPUT -n --line-number and then
iptables -D INPUT <linenumber>