Articles Tagged ‘DNS’

Domain Name System (DNS)

DNS is a very popular and well known protocol. It is used for resolving host names and domain names to IP addresses. The fact is that when you type the name is translated into an IP address via a number of queries that take place from your PC towards the DNS server. This DNS Query process (and more) is analysed in great depth in the articles that follow.

The amount of information covering the DNS protocol has been broken into smaller sections to help avoid confusion and make the learning process as easy as possible.

Following is a break-down of the articles provided and information they contain:

Section 1: The DNS Protocol. How and why the DNS protocol was born. Page contains a bit of historical information and also compares DNS with the OSI Reference model, where you will see the layers on which DNS works. Internet DNS hierarchy is also analysed here, giving you the chance to understand how domains on the Internet are structured.

Section 2: The DNS Resolution Process. What really happens when a host requests a DNS resolution. Full analysis of the whole resolution process using a real life example. Understand Name Servers and the role they play in the DNS system.

Section 3: The DNS Query Message Format. This section, along with the next one gives you the DNS packet format in all its glory. Learn how DNS queries are generated and formatted. See, learn and understand the various fields within the packets as your taken through a full detailed analysis of the packet structure using the cool 3D diagrams.

Section 4: The DNS Response Message Format.This is the continuation of the section above, dealing with the DNS response that's received. You will learn how the response packet is generated, formatted and sent to the resolver. Again, you're taken through a full detailed analysis of the packet structure using the cool 3D diagrams.


Network Protocols

The Protocols section deals with various network protocols found in today's networks.  The aim of this section is to help understand the fundamentals of network protocols, how they work, where they are used and in which way they all work together to provide reliability and functionality for our applications, services and users.

Protocols such as TCP, IP, ICMP others are analysed in greater depth and therefore a dedicated sub-section has been provided, while other protocols are analysed on a single article with compromising its quality.

Palo Alto Networks Firewall - Web & CLI Initial Configuration, Gateway IP, Management Services & Interface, DNS – NTP Setup, Accounts, Passwords, Firewall Registration & License Activation

This article is the second-part of our Palo Alto Networks Firewall technical articles. Our previous article was introduction to Palo Alto Networks Firewall appliances and technical specifications, while this article covers basic IP management interface configuration, DNS, NTP and other services plus account password modification and appliance registration and activation.

The introduction of Next Generation Firewalls has changed the dimension of management and configuration of firewalls, most of the well-known Firewall vendors have done a major revamp, be it the traditional command line mode or the GUI mode.

Palo Alto Networks is no different to many of those vendors, yet it is unique in terms of its WebUI. It’s a whole new experience when you access the WebUI of Palo Alto Networks Next-Generation Firewalls.

In order to start with an implementation of the Palo Alto Networks Next-Generation Firewalls one needs to configure them. Palo Alto Networks Next-Generation Firewalls can be accessed by either an out-of-band management port labelled as MGT or a Serial Console port (similar to Cisco devices). By using the MGT port, one can separate the management functions of the firewall from the data processing functions. All initial configurations must be performed either on out-of-band management interface or by using a serial console port. The serial port has default values of 9600-N-1 and a standard roll over cable can be used to connect to a serial port.

 Palo Alto Networks Firewall PA-5020 Management & Console Port 

Figure 1.   Palo Alto Networks Firewall PA-5020 Management & Console Port

By default, Palo Alto Networks Next-Generation Firewalls use MGT port to retrieve license information and update the threats and application signature, therefore it is imperative the MGT port has proper DNS settings configured and is able to access the internet.

To access the Palo Alto Networks Firewall for the first time through the MGT port, we need to connect a laptop to the MGT port using a straight-thru Ethernet cable. By default, the web gui interface is accessed through the following IP Address and login credentials (note they are in lower case):

  • MGT Port IP Address: /24
  • Username: admin
  • Password: admin

For security reasons it’s always recommended to change the default admin credentials. Until this condition is satisfied, the Palo Alto Networks Firewall alerts the administrator to change the default password every time he logs in, as shown in the screenshot below:

 Palo Alto Networks Firewall alerts the administrator to change the default password

Figure 2. Palo Alto Networks Firewall alerts the administrator to change the default password

Performing the Initial Setup in Palo Alto Networks Firewall Check List

Below is a list of the most important initial setup tasks that should be performed on a Palo Alto Networks Firewall regardless of the model:

  • Change the default login credentials
  • Configure the management IP Address & managed services (https, ssh, icmp etc)
  • Configure DNS & NTP Settings
  • Register and Activate the Palo Alto Networks Firewall

Let’s take a look at each step in greater detail.

Change the Default Login Credentials

Step 1: Establish connectivity with the Palo Alto Networks Firewall by connecting an Ethernet cable between the Management and the laptop’s Ethernet interface.

Step 2: Configure the laptop Ethernet interface with an IP address within the network. Keep in mind that we’ll find the Palo Alto Networks Firewall at so this IP must not be used.

Step 3: Open a web browser and navigate to the URL – Take note that this is an HTTPS site. At this point the Palo Alto Networks Firewall login page appears.

Step 4: Enter admin for both name and password fields.

Step 5: From the main menu, click Device > Administrators > admin

  • Type the old password in the Old Password field
  • Type the new password in the New Password field
  • Type new password in the Confirm New Password field
  • Click ok

Configure The Management IP Address & Management Services (HTTPS, SSH, ICMP)

At this point we have connectivity to the Palo Alto Networks Firewall and need to change the management IP address:

Windows 2003 Server

This category contains articles covering the installation and configuration of Windows 2003 Server services. All articles contain step-by-step screenshots to make them easier to follow. No matter how novice or advanced your knowledge on Windows 2003 Technologies is, following the provided instructions is very easy and straight-forward.

We hope you enjoy the provided articles and welcome your feedback and suggestions.

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Cisco Help

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Windows 2012

  • New Features
  • Licensing
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