What are the ways to secure Linux network

[Angelica Maria]

Hi,
I am very much concerned with network security. I have a dozen of computer connected to a Linux server. The computer are connected internet and filled up with virus. As those have different platform so the attack is obvious. What I am trying to do here is safeguarding my main server on the network with different protection tips. What are the different ways by which I can protect my Linux based PC on the network.

[Steve123]

It is necessary to first determine that your system is safe on network or not. To answer this question, you must list the potential security hole network. Each TCP or UDP port open, can be used to attack your system, and is therefore a potential security hole. You must have proper information on each port open and working on the network. To see which ports are open, run netstat-a.

[Shen]

It is necessary to first determine that your system is safe on network or not. To answer this question, you must list the potential security hole network. Each TCP or UDP port open, can be used to attack your system, and is therefore a potential security hole. You must have proper information on each port open and working on the network. To see which ports are open, run netstat-a.

[Big Fish]

As you give netstat command you can see a list of open connections those in which state = established, and TCP servers listening for incoming connections in the state = listen. Udp servers also listen while LISTEN is not indicated. The column Local Address server listening (LISTEN) is one of the most important by the information it delivers, network interface on which the server is listening or IP address. You have to here determine that what port it listens (numbers or letters after and which indicates the type of service.

[Zachary]

If you run 'netstat-nap' you can even know the names of programs that open these ports can also be used to identify open ports. Like for example there is a login services like www, ftp, printer, syslog turned on the system and also other like ssh (port 22), X11 (port 6000). (Refer to file '/ etc / services' for conversions name <-> port number). You have to concentrate more on the opening ports as they are the opening gateway to your network.

[Snake08]

When the network interface is not properly concerned with the security then anyone can try to connect to this service. This is a bad sign for your safety and you should try to find if the server can establish a list of Access Control (ACL) to secure things.By cons, if network interface is an IP address, it means that the server is not responding to possible connections on the network interface that this IP address.

[Spyrus]

Here is an example for this. You have a localhost ftp, then ftp is connected to the localhost interface (the loopback), and it will not be seen for your Ethernet network or your Internet connection PPP. It is the goal to be reached, because you can run services on your machine without anyone on the Internet can see them. Note therefore that a number of network interface other than localhost is bad because it certainly means that the service can be seen outside of your machine. So check your LCAs then.