Samba: Linux Iptables Firewall Configuration

To configure a Linux firewall to allow connections to a Samba server, you will need to open the necessary ports in the firewall. Samba uses the following ports:

• 137/udp: NetBIOS name service
• 138/udp: NetBIOS datagram service
• 139/tcp: NetBIOS session service
• 445/tcp: SMB over TCP

To open these ports in the iptables firewall, you can use the following commands:

iptables -A INPUT -p udp --dport 137 -j ACCEPT
iptables -A INPUT -p udp --dport 138 -j ACCEPT
iptables -A INPUT -p tcp --dport 139 -j ACCEPT
iptables -A INPUT -p tcp --dport 445 -j ACCEPT

These commands will allow incoming connections to the specified ports. Be sure to allow only the ports that you need to expose to the network.

It is also a good idea to limit access to the Samba ports to specific IP addresses or subnets if possible. This can be done by specifying the source IP address or subnet in the iptables rule, like this:

iptables -A INPUT -p udp --dport 137 -s 10.0.0.0/24 -j ACCEPT

This will allow incoming connections to port 137 only from IP addresses in the 10.0.0.0/24 subnet.

Remember to save your firewall rules after making any changes, so that they will be applied on boot. You can do this using the iptables-save command.