CentOS / RedHat Linux server and by default firewall blocked out everything including telnet access. How do I allow telnet – port 23 thought Linux iptables firewall ?
Method 1:
Login as root account and type the following command
[root@lifelinux ~]# iptables -A INPUT -m state --state NEW -p tcp --dport 23 -j ACCEPT
Save rule to /etc/sysconfig/iptables
[root@lifelinux ~]# iptables-save > /etc/sysconfig/iptables
Method 2:
Login as the root user and open /etc/sysconfig/iptables file, enter:
[root@lifelinux ~]# vi /etc/sysconfig/iptables
Add the following line:
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 23 -j ACCEPT
The final:
Save and close the file. Restart the firewall:
[root@lifelinux ~]# /etc/init.d/iptables restart
Related Posts:
- How Do I Block An IP Address On Linux Server ?
- How To Flush/Remove All Iptables Rules In Linux
- How to install IPTables on RedHat / Centos Linux