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Linux Iptables Open LDAP Server TCP Ports 389 and 636

The default Iptables configuration under CentOS / Red Hat / RHEL / Fedora Linux does not allow inbound access to LDAP service. How do I update iptables settings to allow access to the LDAP primary TCP #389 and encrypted-only TCP # 636 ports, while keeping all other ports on the server in their default protected state?
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Snmpd Listen to Specific IP Address ( BIND To Selected Interfaces )

How do I force SNMP (Simple Network Management Protocol) network management software to listen on public interfaces under RHEL / RedHat / Fedora / CentOS Linux server?
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Iptables Open VNC Port To Allow Incoming VNC Connections

How do I configure Linux system firewall to allow incoming VNC connections?
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Samba Restrict IPC$ ( list of shared resources )

The IPC$ share allows users to anonymously fetch a list of shared resources from a server. It can be used as a point of attack into a system. How do I disable or limit IPC$ under Samba to certain subnet such as
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CentOS / Red Hat Configure an NTP Client And Server

How do I configure an NTP (Network Time Protocol) client or server under CentOS / RHEL / Fedora Linux to manage the system clock over a network?
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Linux Iptables Allow NFS Clients to Access the NFS Server

The portmapper assigns each NFS service to a port dynamically at service startup time. How do I allow legitimate NFS clients to access the NFS server using RHEL / Fedora / CentOS Linux 5.x iptables firewall?
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Understanding CentOS Default -A RH-Firewall-1-INPUT -p 50 -j ACCEPT Firewall Rule

Q.Can you explain the meaning of following two firewall rules present in my /etc/sysconfig/iptables rules under CentOS Enterprise Linux version 5.2?

-A RH-Firewall-1-INPUT -p 50 -j ACCEPT
-A RH-Firewall-1-INPUT -p 51 -j ACCEPT
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Start Iptables Under Linux

How do I start Iptables firewall under RHEL / Red Hat / CentOS / Fedora Linux from a shell prompt? How do I stop firewall? How do I start or restart firewall on a bash shell?
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Linux Open Port 80 (HTTP Web Server Port)

I am new CentOS/RHEL 5.x/6.x user. How do I open port 80 (Apache Web Server) under Red Hat / CentOS / Fedora Linux?
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How do I Load / Start RHEL / CentOS / Fedora Linux Iptables Firewall on Computer Boot?

Q. I'd like to start my Iptables based firewall when my computer comes online so that it get protected from the Internet? I'm using CentOS Linux Server version 4.x.

A. CentOS / RHEL / Fedora Linux has service located at /etc/init.d/iptables to start firewall on boot. All you have to do is type the following command to turn on firewall on boot:
# chkconfig iptables on

Your firewall rules are saved at /etc/sysconfig/iptables files.