Video Description

Network Naming In this section, we take a look at network naming. We will learn the functions and capabilities the Domain Name System, discusses how to configure and troubleshoot Windows Internet Naming Service, and explore how we can use common TCP/IP utilities to troubleshoot issues with DNS and WINS. Computers use IP addresses to communicate with each other, but people are more inclined to remember names than long sequences of seemingly random numbers. To solve this, we have a system called "name resolution" that converts names into IP addresses and back again. Domain Name System, or DNS, is the main protocol used for name resolution, and Windows, Linux, and Macintosh OS X continue to support another protocol called Windows Internet Name Server (WINS for short). Before DNS this information was stored on what is called a HOSTS file. As no single computer can handle all DNS resolution, the task is delegated to top-dogs in the industry and subsidiary DNS systems. DNS name servers run the software, DNS zones contain records for single DNS domain's, and DNS records work to map Fully Qualified Domain Name's to IP addresses. Name resolution is not completely necessary, but it is crucial towards making the internet accessible and easy to use for humans. To test name resolution, try typing a web address into a browser. Via broadcasting, HOSTS files, or querying a DNS server, the name should resolve to an IP address and load the home page. Every client needs an IP address, subnet mask, default gateway, and at least one DNS server. Typing "ipconfig" into the Windows console will provide you with all the DNS information on your machine. DNS servers store data in cached lookups, forward lookup zones, and reverse lookup zones. How can we use TCP/IP utilities as well in order to troubleshoot issues with DNS and WINS? For one, do not use your web browser for troubleshooting. Instead, use the "ipconfig" and "flushdns" commands in the Windows command console. You can also use the "ping" command followed by a well-known website like in order to test your DNS connection. In UNIX and Linux you can use the domain information groper (DIG), which is similar to "nslookup", in order to troubleshoot DNS. Most DNS problems stem from improper configuration, and it is important to carry out the same steps when troubleshooting regardless of what the user cannot connect to. Troubleshooting TCP/IP involves diagnosing the Network Interface Controller (NIC), diagnosing locally, checking the IP and subnet mask, running "netstat" with no options, running "netstat –s", diagnosing to the gateway, and finally diagnosing to the internet. After doing all of this, running the "tracert" with the target IP will show you if it is possible to connect and the hops the connection takes to get there. Lastly, use your common sense and consider all the obvious factors first if you are having trouble fixing DNS issues.

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