linux based network proposal

A Presentation and Demonstration

LINUXPROJECT.COM

MEMBERS AND THEIR OBJECTIVES

• Robert Banning• DNS & DHCP (dnsmasq)

• Chris Riccio• Apache , https (httpd) & E-Mail (postfix, dovecot, &

squirrelmail)

• Casey Adams• Shell scripts & SSH (sshd)

• Salvatore Mauro• NFS (nfs) & FTP (vsftpd)

• Barbara Schwerdtmann• VNC & Samba (smb)

PHYSICAL LAYOUT AND IP ADDRESSING SCHEME

Dynamic Host Configuration Protocol (DHCP)

Topics DHCP defined How DHCP works Configuration

DHCP Defined

DHCP is a network application protocol used by devices that automatically assigns temporary IP addresses to client machines logging into an IP network. The IP addresses assigned to clients are unique but as devices leave and re-join the network the addresses are released and reused.

How DHCP Works

Domain Name System (DNS)

Topics DNS defined How DNS works Configuration

DNS Defined

DNS is the way that Internet domain names are located and translated into Internet Protocol addresses. DNS basically is a database that has a list of domain names with IP addresses. (example phone book)

How DNS Works

Translates hostnames such as www.linuxproject.com into IP addresses which will allow the delivery of information from one computer to another. Without DNS the internet would not be possible unless you had the IP addresses for each link memorized. It also stores a listing of mail exchange servers which will allow e-mail to be possible.

Important Files

Resolv.conf

Located in /etc directory

Contains IPs of domain name servers

Named.conf

Configuration file in BIND

Defines the name server with name and ip address of the hosts

http://www.linuxproject.com/

DnsmasqFirst Step: Check IP address in the resolv.conf file on your local name server

nameserver 12.345.678.8


Second Step: On all local PC’s vim /etc/resolv.conf and type only this


Third Step: Vim /etc/hosts and enter your IP addresses and domain names

127.0.0.1 localhost

192.168.0.1 server

192.168.0.2 server2

192.168.0.3 server3

192.168.0.4 fedora

192.168.0.5 windows

192.168.0.2 ftp

192.168.0.1 mail

Fourth Step: vim /etc/dnsmasq.conf un-comment the following lines and replace the stand in text with your own

expand-hosts

domain=test.net (use your domain name here)

dhcp-range=192.168.0.4,192.168.0.10,168 (first three IP address .1,.2,.3 are statically assigned to servers)

Apache: Web Server

Topics

•Apache defined

•How a web server (Apache) works

•Web server security

Apache: Defined

•Apache is a web server notable for playing a key role in the initial growth of the World Wide Web.

•Apache is fast, secure, and infinitely customizable.

•Since April of 1996, Apache has been the most popular HTTP server on the World Wide Web.

How a web-server works…

1. The browser broke the URL into three parts:

1. The protocol ("http")

2. The server name ("www.linuxproject.com")

3. The file name (“index.php")

2. The browser communicated with a name server to translate the server name

"www.linuxproject.com" into an IP address, which it uses to connect to the

server machine.

3. The browser then formed a connection to the server at that IP address on port

80.

1. Client Machine

2. DNS Server

3. Web Server

Apache Security

-HTTPS1. Hyper Text Transfer Protocol Secure is

designed to create a secure connection over an unsecure network

• HTTP over SSL (secure and encrypted)

-htaccess1. htaccess is designed for directory level

access control

• This will prompt each user who access the website to enter their previously assigned credentials

E-Mail

•We implemented a simple web-based email GUI (graphical user interface) called squirrelmail

•Very familiar to services such as Google’s Gmail or Microsoft's Live email

•Each user can login from any machine on the LAN and access all of their email securely

Shell Script

Topics

Shell Scripts Defined Purpose of our Shell Script Secure Copy Shell Script

Shell Scripts Defined

A series of commands written in plain text file for a shell, or command line interpreter, of an operating system.

The Purpose of Our Shell Script

Copy files from one server to the another server

Secure Password Shell Script scp /share/TITAN/* criccio@server2:/share/THEBES

Secure Shell (SSH)

TOPICS

SSH Defined How SSH Works

SSH Defined

Set of programs that use public/private key technology for authenticating and encrypting

between user accounts on distributed hosts on the internet.

How SSH Works

Client connects to server Server sends to client:

Public Host Key Public Server Key

Client generates random 256 bit key and encrypts it with both public host and server key

Client sends it back to server Server decrypts with own private host

and server key

FTP & NFS

FTP

FTP is based on the client-server model of communication between computers: one computer runs a server program that makes information available to other computers.

The other computers run client programs that request information and receive replies from the server.

To access an FTP server, users must be able to connect to the Internet or an intranet (via a modem or local area network) with an FTP client program.

NFS

The Network File System (NFS) software allows one computer (an NFS client) attached to a network to access the files on the hard disk of another computer on the same network.

An NFS client can mount the whole or part of a remote file system. It can then access the files in this file system almost as if they were present on a local hard disk.

FTP vs. NFS

The main differences between FTP and NFS are:

FTP uses actual file transfers having users upload and download them.

NFS is actual real-time file sharing between workstations within a network

NFS/FTP Diagrams

` FTP Connections

S M B

SMB, (Service Message Block), is a protocol, as well as a suite of programs that allow Linux servers to share files, printers, and other resources with Window clients.

Samba is also open source software, and a safe way to share files over an secured /

secured internet.

Samba

Another benefit Samba gives us is the ability to act as an interface. A graphical

interface to access files, folders.. etc, without having to go through the

command line.

VNC

What is VNC? VNC is stands for Virtual Network

Computing.

It is a graphical desktop sharing system, used to control another computer over the

network via remote access.

VNC

VNC is platform independent. Meaning, it will work with most operating systems. In

the case of Microsoft, a proprietary operating system, the use of the RFB

Protocol, or {remote frame-buffer} allows VNC to work with all windows systems,

applications, and MAC operating systems.

Thank You

linux based network proposal

Technology