Changes

= Some DNS Review =DOMAIN NAME SYSTEM RESOURCES==

Also if you didn't become comfortable using the '''dig''' tool - you'll get more practice with it now*[https://en.wikipedia.org/wiki/Test_case Test Case Definition] (Wikipedia definition of a Test Case)

Find Last week you were introduced to administering a simple authoritative DNS server. This week we will review that topic, but focus on learning a few more resource record types. This lab will also provide the MX record for senecacollegebackground and tools (such as a test case) that will be used in your assignment #1.ca using dig:

<source lang="bash">You will also be using the '''dig senecacollege''' tool in more depth in this lab.ca MX</source>

Notice that the response for your dig commainds for === The MX records contains domain names and not IP addresses. That means that when you look for a domain's email server - you may need to do a query for MX and another for A.Record ===

You should When someone tries to send email (for example: '''senecacollege.ca''') the mail message needs to be comfortable reading and writing an MX record in sent to the Bind configuration file. See [http:/Seneca <u>mail</www.zytraxu> server (which, most likely, is '''not''' senecacollege.com/books/dns/ch8/mxca).html That is the reference] typical setup for any business since using a different server for the syntaxmail simplifies administration and helps maintain server load balancing.

Sometimes you want multiple domain names to point to :Find the same serverMX record for senecacollege. The most common example of this is ca using the www'''dig''' command:<br><source lang="bash">dig senecacollege. ca MX</source>:Notice that the email servers aren't even a subdomainof senecacollege. Use dig to find ca but a completely different company (Microsoft in this case).<br>In other cases (for example, check the main web server records for Seneca or for CBC''google.com'') the email servers are within the company's domain.

See [httpIn rare cases, there may be no MX records associated with a domain (For example://wwwtry '''dig littlesvr.zytraxca''').com/books/dns/ch8/cnameIn this latter case, the server called littlesvr.html ca, which is supporting a web-server, is also supporting the reference] email server for CNAME to get examples of how to configure such records in Bindthe same IPADDR.

== TXT Notice that the response from commands for '''MX records''' contains <u>domain names</u> and <u>not</u> IP addresses. That means that when you look for a domain's email server, you may be required to also perform a query for MX record ==as well as for another type A record. Recall that type A records provide the IPADDR information.

A TXT It is highly recommended that you become comfortable with being able to create an MX records, and be comfortable interpreting (reading) MX record can store pretty much anythinginformation contained in the '''Bind configuration file''' or by performing domain name queries using '''dig''', it's typically used for purposes that ''nslookup''' or the desiners of DNS haven't though of themselves''host''' command. For example a common use of a TXT record is SPFSee [http: a record that helps receiving email servers to determine //www.zytrax.com/books/dns/ch8/mx.html the reference] for the likelyhood that a message is spamsyntax.

== Your task = The CNAME record ===

Sometimes you may want to create multiple domain names to point to the same server. The most common example of this is the '''www. subdomain'''. Use the '''dig''' command to find the <u>main web server</u> for '''Seneca College''' as well as for the '''CBC (Canadian Broadcast Corporation)'''. See [http://www.zytrax.com/books/dns/ch8/cname.html the reference] for CNAME to view examples of how to configure such records in Bind. === The TXT record === A '''TXT''' record is used to store any type of data or information. It is generally considered to be a "user-defined" section in order to provide additional information that the DNS system was not designed to handle or accommodate. For example, a common use of the TXT record is to support '''SPF''': which is a special type of record used to help receiving email servers determine the likelihood that a message is spam. === Update Additional Resource Records for Your VM1 Name Server === Configure at least one of your '''VM1''' machine (Bind server) to incorporate each of the records discussed above and verify that your records work by DNS query. '''Record steps, commands, and your observations in INVESTIGATION 1 in your OPS335 lab log-book'''  ==INVESTIGATION 2: GENERATING TEST PLANS== === Reason for Using Test Plans === Every IT company needs to perform testing whether on software they create, or for the systems they set up in order to provide quality assurance. Whenever an IT job is performed, it is essential that there is a method or framework to show that your job is complete and correct (according to original expectations). One example would be the use of a '''Test Plan''' in order to <u>demonstrate</u> that the task was completed successfully according to the required specifications (i.e. proof). Another example would include the use of a ''ticketing system'' that tracks issues to be addressed, fixed, closed, and end-user feedback. How much detail goes into the test plan depends on what resources are available for testing, the scale of the changes, and the risk associated with problems that may occur while performing a task. In your domain served by case, the worst case scenerio is that you mis-configure your server, and that you may lose a few marks on an assignment. In the IT industry, a mistake (such as server mis-configuration) can cost the company that you work a lot of money (perhaps even more than your salary). Your test plan that you create should be planned, be well organized (communicated) and contain the appropriate test cases to indicate that the configuration was successful. === Test Cases Within a Test Plan === Theoretically, you will create test cases (to be included in your Test Plan) prior to finishing the configuration of your system or task. One way to look at this is that when all of the test cases are created prior to completing your task, they become a benchmark or framework which really determine the requirements for your system. Generally, each test case typically has at least '''one expected positive''' and a '''few expected negative''' results. For example, if you are setting up a DNS record for www.yoursenecaid.org your test case might look something like this:<br><br> [[Image:Sample_test_case.png|800px| ]] <br><br>The test above shows a few things: that the DNS server is running, that it's accessible from the internal network, and it is serving the correct record. It also shows that the needed record does not propagate to the public DNS servers - the server 8.8.8.8 doesn't have the Bind same record that your private server does. That's not a wonderful result but it's what you were expecting so it's still a positive result. In fact if 8.8.8.8 returned an A record for your query - you should be concerned that the rest of your test cases may be incorrect. You can spend an infinite amount of time running tests and stil not prove anything definitively, so you have to do your best to make sure the tests you run are representative of the requirements - that after a successful run of all the tests the service is almost certainly working correctly. === Identifying Test Case Failures === Test cases (in a test suite) are not intended to only show that the system is working. On the other hand, it is valuable to view a history of problems or failures that have occurred in the past. For those situations, there may be a bug tracking number or some other means of tracking down what caused the problem in the past and how it was fixed. This can help provide quick identification of problems to lead to quick resolutions in case those similar situation occur in the future. === Create Test Cases for Your VM1 Machine === Provide query results for your '''vm1 ''' name server for each of the resource records discussed in this lab. Pick any section of any of the labs that wish to generate 3 separate test cases. Write the test cases in a test plan template, then save another copy of the test plan, making sure to include:your current testing criteria, and verify the results from you running that current testing criteria. You will be required to show this test plan upon sign-off of this lab. '''Record steps, commands, and your observations in INVESTIGATION 2 in your OPS335 lab log-book'''  = COMPLETING THE LAB = To submit the lab, show the '''newly-created DNS records work''' (via nslookup, host, or dig command), and show your '''completed test plan'''.  =EXPLORATION QUESTIONS= #What is the purpose of the following types resource records?<ul><li>A</li><li>NS</li><li>MX</li><li>TXT</li><li>PTR</li></ul>#Show the steps for using '''nslookup''' for querying the name name cnn.com for each of the record types discussed in the previous question.#Show the '''host''' commands for querying the name name cnn.com for each of the record types discussed in Question #1.#Show the '''dig''' commands for querying the name name cnn.com for each of the record types discussed in Question #1.#What is the purpose of a Test Plan?#What are the main components of a Test Plan?